diff --git a/README.md b/README.md
index 257337d2ca3..cb3b9f8110e 100644
--- a/README.md
+++ b/README.md
@@ -33,10 +33,8 @@ In Node.js
 ----------
 
 Ensure you have the latest LTS version of Node.js installed.
-
-This SDK targets Node 12 for compatibility, which translates to ES6. If you're using
-a bundler like webpack you'll likely have to transpile dependencies, including this
-SDK, to match your target browsers.
+This library relies on `fetch` which is available in Node from v18.0.0 - it should work fine also with polyfills.
+If you wish to use a ponyfill or adapter of some sort then pass it as `fetchFn` to the MatrixClient constructor options.
 
 Using `yarn` instead of `npm` is recommended. Please see the Yarn [install guide](https://classic.yarnpkg.com/en/docs/install)
 if you do not have it already.
diff --git a/package.json b/package.json
index fda529c9147..710bb281d87 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "version": "20.1.0",
   "description": "Matrix Client-Server SDK for Javascript",
   "engines": {
-    "node": ">=12.9.0"
+    "node": ">=16.0.0"
   },
   "scripts": {
     "prepublishOnly": "yarn build",
@@ -55,14 +55,12 @@
   "dependencies": {
     "@babel/runtime": "^7.12.5",
     "another-json": "^0.2.0",
-    "browser-request": "^0.3.3",
     "bs58": "^5.0.0",
     "content-type": "^1.0.4",
     "loglevel": "^1.7.1",
     "matrix-events-sdk": "^0.0.1-beta.7",
     "p-retry": "4",
     "qs": "^6.9.6",
-    "request": "^2.88.2",
     "unhomoglyph": "^1.0.6"
   },
   "devDependencies": {
@@ -81,9 +79,9 @@
     "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.13.tgz",
     "@types/bs58": "^4.0.1",
     "@types/content-type": "^1.1.5",
+    "@types/domexception": "^4.0.0",
     "@types/jest": "^29.0.0",
     "@types/node": "16",
-    "@types/request": "^2.48.5",
     "@typescript-eslint/eslint-plugin": "^5.6.0",
     "@typescript-eslint/parser": "^5.6.0",
     "allchange": "^1.0.6",
@@ -92,6 +90,7 @@
     "better-docs": "^2.4.0-beta.9",
     "browserify": "^17.0.0",
     "docdash": "^1.2.0",
+    "domexception": "^4.0.0",
     "eslint": "8.24.0",
     "eslint-config-google": "^0.14.0",
     "eslint-import-resolver-typescript": "^3.5.1",
@@ -104,7 +103,7 @@
     "jest-mock": "^27.5.1",
     "jest-sonar-reporter": "^2.0.0",
     "jsdoc": "^3.6.6",
-    "matrix-mock-request": "^2.1.2",
+    "matrix-mock-request": "^2.5.0",
     "rimraf": "^3.0.2",
     "terser": "^5.5.1",
     "tsify": "^5.0.2",
@@ -115,6 +114,9 @@
     "testMatch": [
       "<rootDir>/spec/**/*.spec.{js,ts}"
     ],
+    "setupFilesAfterEnv": [
+      "<rootDir>/spec/setupTests.ts"
+    ],
     "collectCoverageFrom": [
       "<rootDir>/src/**/*.{js,ts}"
     ],
diff --git a/spec/TestClient.ts b/spec/TestClient.ts
index 0a6c4e0eee2..6056884dd31 100644
--- a/spec/TestClient.ts
+++ b/spec/TestClient.ts
@@ -30,7 +30,6 @@ import { MockStorageApi } from "./MockStorageApi";
 import { encodeUri } from "../src/utils";
 import { IDeviceKeys, IOneTimeKey } from "../src/crypto/dehydration";
 import { IKeyBackupSession } from "../src/crypto/keybackup";
-import { IHttpOpts } from "../src/http-api";
 import { IKeysUploadResponse, IUploadKeysRequest } from '../src/client';
 
 /**
@@ -56,11 +55,11 @@ export class TestClient {
         this.httpBackend = new MockHttpBackend();
 
         const fullOptions: ICreateClientOpts = {
-            baseUrl: "http://" + userId + ".test.server",
+            baseUrl: "http://" + userId?.slice(1).replace(":", ".") + ".test.server",
             userId: userId,
             accessToken: accessToken,
             deviceId: deviceId,
-            request: this.httpBackend.requestFn as IHttpOpts["request"],
+            fetchFn: this.httpBackend.fetchFn as typeof global.fetch,
             ...options,
         };
         if (!fullOptions.cryptoStore) {
diff --git a/spec/browserify/sync-browserify.spec.ts b/spec/browserify/sync-browserify.spec.ts
index 8a087c80722..648a72dc416 100644
--- a/spec/browserify/sync-browserify.spec.ts
+++ b/spec/browserify/sync-browserify.spec.ts
@@ -14,46 +14,66 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-// load XmlHttpRequest mock
+import HttpBackend from "matrix-mock-request";
+
 import "./setupTests";
 import "../../dist/browser-matrix"; // uses browser-matrix instead of the src
-import * as utils from "../test-utils/test-utils";
-import { TestClient } from "../TestClient";
+import type { MatrixClient, ClientEvent } from "../../src";
 
 const USER_ID = "@user:test.server";
 const DEVICE_ID = "device_id";
 const ACCESS_TOKEN = "access_token";
 const ROOM_ID = "!room_id:server.test";
 
+declare global {
+    // eslint-disable-next-line @typescript-eslint/no-namespace
+    namespace NodeJS {
+        interface Global {
+            matrixcs: {
+                MatrixClient: typeof MatrixClient;
+                ClientEvent: typeof ClientEvent;
+            };
+        }
+    }
+}
+
 describe("Browserify Test", function() {
-    let client;
-    let httpBackend;
+    let client: MatrixClient;
+    let httpBackend: HttpBackend;
 
     beforeEach(() => {
-        const testClient = new TestClient(USER_ID, DEVICE_ID, ACCESS_TOKEN);
-
-        client = testClient.client;
-        httpBackend = testClient.httpBackend;
+        httpBackend = new HttpBackend();
+        client = new global.matrixcs.MatrixClient({
+            baseUrl: "http://test.server",
+            userId: USER_ID,
+            accessToken: ACCESS_TOKEN,
+            deviceId: DEVICE_ID,
+            fetchFn: httpBackend.fetchFn as typeof global.fetch,
+        });
 
         httpBackend.when("GET", "/versions").respond(200, {});
         httpBackend.when("GET", "/pushrules").respond(200, {});
         httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
-
-        client.startClient();
     });
 
     afterEach(async () => {
         client.stopClient();
-        httpBackend.stop();
+        client.http.abort();
+        httpBackend.verifyNoOutstandingRequests();
+        httpBackend.verifyNoOutstandingExpectation();
+        await httpBackend.stop();
     });
 
-    it("Sync", function() {
-        const event = utils.mkMembership({
-            room: ROOM_ID,
-            mship: "join",
-            user: "@other_user:server.test",
-            name: "Displayname",
-        });
+    it("Sync", async () => {
+        const event = {
+            type: "m.room.member",
+            room_id: ROOM_ID,
+            content: {
+                membership: "join",
+                name: "Displayname",
+            },
+            event_id: "$foobar",
+        };
 
         const syncData = {
             next_batch: "batch1",
@@ -71,11 +91,16 @@ describe("Browserify Test", function() {
         };
 
         httpBackend.when("GET", "/sync").respond(200, syncData);
-        return Promise.race([
-            httpBackend.flushAllExpected(),
-            new Promise((_, reject) => {
-                client.once("sync.unexpectedError", reject);
-            }),
-        ]);
+        httpBackend.when("GET", "/sync").respond(200, syncData);
+
+        const syncPromise = new Promise(r => client.once(global.matrixcs.ClientEvent.Sync, r));
+        const unexpectedErrorFn = jest.fn();
+        client.once(global.matrixcs.ClientEvent.SyncUnexpectedError, unexpectedErrorFn);
+
+        client.startClient();
+
+        await httpBackend.flushAllExpected();
+        await syncPromise;
+        expect(unexpectedErrorFn).not.toHaveBeenCalled();
     }, 20000); // additional timeout as this test can take quite a while
 });
diff --git a/spec/integ/matrix-client-methods.spec.ts b/spec/integ/matrix-client-methods.spec.ts
index fdf32d9e985..5bec405cbdd 100644
--- a/spec/integ/matrix-client-methods.spec.ts
+++ b/spec/integ/matrix-client-methods.spec.ts
@@ -16,13 +16,12 @@ limitations under the License.
 import HttpBackend from "matrix-mock-request";
 
 import * as utils from "../test-utils/test-utils";
-import { CRYPTO_ENABLED, MatrixClient, IStoredClientOpts } from "../../src/client";
+import { CRYPTO_ENABLED, IStoredClientOpts, MatrixClient } from "../../src/client";
 import { MatrixEvent } from "../../src/models/event";
-import { Filter, MemoryStore, Room } from "../../src/matrix";
+import { Filter, MemoryStore, Method, Room, SERVICE_TYPES } from "../../src/matrix";
 import { TestClient } from "../TestClient";
 import { THREAD_RELATION_TYPE } from "../../src/models/thread";
 import { IFilterDefinition } from "../../src/filter";
-import { FileType } from "../../src/http-api";
 import { ISearchResults } from "../../src/@types/search";
 import { IStore } from "../../src/store";
 
@@ -65,28 +64,27 @@ describe("MatrixClient", function() {
 
     describe("uploadContent", function() {
         const buf = Buffer.from('hello world');
+        const file = buf;
+        const opts = {
+            type: "text/plain",
+            name: "hi.txt",
+        };
+
         it("should upload the file", function() {
             httpBackend!.when(
                 "POST", "/_matrix/media/r0/upload",
             ).check(function(req) {
                 expect(req.rawData).toEqual(buf);
                 expect(req.queryParams?.filename).toEqual("hi.txt");
-                if (!(req.queryParams?.access_token == accessToken ||
-                        req.headers["Authorization"] == "Bearer " + accessToken)) {
-                    expect(true).toBe(false);
-                }
+                expect(req.headers["Authorization"]).toBe("Bearer " + accessToken);
                 expect(req.headers["Content-Type"]).toEqual("text/plain");
                 // @ts-ignore private property
                 expect(req.opts.json).toBeFalsy();
                 // @ts-ignore private property
                 expect(req.opts.timeout).toBe(undefined);
-            }).respond(200, "content", true);
+            }).respond(200, '{"content_uri": "content"}', true);
 
-            const prom = client!.uploadContent({
-                stream: buf,
-                name: "hi.txt",
-                type: "text/plain",
-            } as unknown as FileType);
+            const prom = client!.uploadContent(file, opts);
 
             expect(prom).toBeTruthy();
 
@@ -96,8 +94,7 @@ describe("MatrixClient", function() {
             expect(uploads[0].loaded).toEqual(0);
 
             const prom2 = prom.then(function(response) {
-                // for backwards compatibility, we return the raw JSON
-                expect(response).toEqual("content");
+                expect(response.content_uri).toEqual("content");
 
                 const uploads = client!.getCurrentUploads();
                 expect(uploads.length).toEqual(0);
@@ -107,28 +104,6 @@ describe("MatrixClient", function() {
             return prom2;
         });
 
-        it("should parse the response if rawResponse=false", function() {
-            httpBackend!.when(
-                "POST", "/_matrix/media/r0/upload",
-            ).check(function(req) {
-                // @ts-ignore private property
-                expect(req.opts.json).toBeFalsy();
-            }).respond(200, { "content_uri": "uri" });
-
-            const prom = client!.uploadContent({
-                stream: buf,
-                name: "hi.txt",
-                type: "text/plain",
-            } as unknown as FileType, {
-                rawResponse: false,
-            }).then(function(response) {
-                expect(response.content_uri).toEqual("uri");
-            });
-
-            httpBackend!.flush('');
-            return prom;
-        });
-
         it("should parse errors into a MatrixError", function() {
             httpBackend!.when(
                 "POST", "/_matrix/media/r0/upload",
@@ -141,11 +116,7 @@ describe("MatrixClient", function() {
                 "error": "broken",
             });
 
-            const prom = client!.uploadContent({
-                stream: buf,
-                name: "hi.txt",
-                type: "text/plain",
-            } as unknown as FileType).then(function(response) {
+            const prom = client!.uploadContent(file, opts).then(function(response) {
                 throw Error("request not failed");
             }, function(error) {
                 expect(error.httpStatus).toEqual(400);
@@ -157,30 +128,18 @@ describe("MatrixClient", function() {
             return prom;
         });
 
-        it("should return a promise which can be cancelled", function() {
-            const prom = client!.uploadContent({
-                stream: buf,
-                name: "hi.txt",
-                type: "text/plain",
-            } as unknown as FileType);
+        it("should return a promise which can be cancelled", async () => {
+            const prom = client!.uploadContent(file, opts);
 
             const uploads = client!.getCurrentUploads();
             expect(uploads.length).toEqual(1);
             expect(uploads[0].promise).toBe(prom);
             expect(uploads[0].loaded).toEqual(0);
 
-            const prom2 = prom.then(function(response) {
-                throw Error("request not aborted");
-            }, function(error) {
-                expect(error).toEqual("aborted");
-
-                const uploads = client!.getCurrentUploads();
-                expect(uploads.length).toEqual(0);
-            });
-
             const r = client!.cancelUpload(prom);
             expect(r).toBe(true);
-            return prom2;
+            await expect(prom).rejects.toThrow("Aborted");
+            expect(client.getCurrentUploads()).toHaveLength(0);
         });
     });
 
@@ -202,6 +161,30 @@ describe("MatrixClient", function() {
             client!.joinRoom(roomId);
             httpBackend!.verifyNoOutstandingRequests();
         });
+
+        it("should send request to inviteSignUrl if specified", async () => {
+            const roomId = "!roomId:server";
+            const inviteSignUrl = "https://id.server/sign/this/for/me";
+            const viaServers = ["a", "b", "c"];
+            const signature = {
+                sender: "sender",
+                mxid: "@sender:foo",
+                token: "token",
+                signatures: {},
+            };
+
+            httpBackend!.when("POST", inviteSignUrl).respond(200, signature);
+            httpBackend!.when("POST", "/join/" + encodeURIComponent(roomId)).check(request => {
+                expect(request.data.third_party_signed).toEqual(signature);
+            }).respond(200, { room_id: roomId });
+
+            const prom = client.joinRoom(roomId, {
+                inviteSignUrl,
+                viaServers,
+            });
+            await httpBackend!.flushAllExpected();
+            expect((await prom).roomId).toBe(roomId);
+        });
     });
 
     describe("getFilter", function() {
@@ -676,7 +659,7 @@ describe("MatrixClient", function() {
             // The vote event has been copied into the thread
             const eventRefWithThreadId = withThreadId(
                 eventPollResponseReference, eventPollStartThreadRoot.getId());
-            expect(eventRefWithThreadId.threadId).toBeTruthy();
+            expect(eventRefWithThreadId.threadRootId).toBeTruthy();
 
             expect(threaded).toEqual([
                 eventPollStartThreadRoot,
@@ -1178,15 +1161,150 @@ describe("MatrixClient", function() {
             expect(await prom).toStrictEqual(response);
         });
     });
+
+    describe("logout", () => {
+        it("should abort pending requests when called with stopClient=true", async () => {
+            httpBackend.when("POST", "/logout").respond(200, {});
+            const fn = jest.fn();
+            client.http.request(Method.Get, "/test").catch(fn);
+            client.logout(true);
+            await httpBackend.flush(undefined);
+            expect(fn).toHaveBeenCalled();
+        });
+    });
+
+    describe("sendHtmlEmote", () => {
+        it("should send valid html emote", async () => {
+            httpBackend.when("PUT", "/send").check(req => {
+                expect(req.data).toStrictEqual({
+                    "msgtype": "m.emote",
+                    "body": "Body",
+                    "formatted_body": "<h1>Body</h1>",
+                    "format": "org.matrix.custom.html",
+                    "org.matrix.msc1767.message": expect.anything(),
+                });
+            }).respond(200, { event_id: "$foobar" });
+            const prom = client.sendHtmlEmote("!room:server", "Body", "<h1>Body</h1>");
+            await httpBackend.flush(undefined);
+            await expect(prom).resolves.toStrictEqual({ event_id: "$foobar" });
+        });
+    });
+
+    describe("sendHtmlMessage", () => {
+        it("should send valid html message", async () => {
+            httpBackend.when("PUT", "/send").check(req => {
+                expect(req.data).toStrictEqual({
+                    "msgtype": "m.text",
+                    "body": "Body",
+                    "formatted_body": "<h1>Body</h1>",
+                    "format": "org.matrix.custom.html",
+                    "org.matrix.msc1767.message": expect.anything(),
+                });
+            }).respond(200, { event_id: "$foobar" });
+            const prom = client.sendHtmlMessage("!room:server", "Body", "<h1>Body</h1>");
+            await httpBackend.flush(undefined);
+            await expect(prom).resolves.toStrictEqual({ event_id: "$foobar" });
+        });
+    });
+
+    describe("forget", () => {
+        it("should remove from store by default", async () => {
+            const room = new Room("!roomId:server", client, userId);
+            client.store.storeRoom(room);
+            expect(client.store.getRooms()).toContain(room);
+
+            httpBackend.when("POST", "/forget").respond(200, {});
+            await Promise.all([
+                client.forget(room.roomId),
+                httpBackend.flushAllExpected(),
+            ]);
+            expect(client.store.getRooms()).not.toContain(room);
+        });
+    });
+
+    describe("getCapabilities", () => {
+        it("should cache by default", async () => {
+            httpBackend!.when("GET", "/capabilities").respond(200, {
+                capabilities: {
+                    "m.change_password": false,
+                },
+            });
+            const prom = httpBackend!.flushAllExpected();
+            const capabilities1 = await client!.getCapabilities();
+            const capabilities2 = await client!.getCapabilities();
+            await prom;
+
+            expect(capabilities1).toStrictEqual(capabilities2);
+        });
+    });
+
+    describe("getTerms", () => {
+        it("should return Identity Server terms", async () => {
+            httpBackend!.when("GET", "/terms").respond(200, { foo: "bar" });
+            const prom = client!.getTerms(SERVICE_TYPES.IS, "http://identity.server");
+            await httpBackend!.flushAllExpected();
+            await expect(prom).resolves.toEqual({ foo: "bar" });
+        });
+
+        it("should return Integrations Manager terms", async () => {
+            httpBackend!.when("GET", "/terms").respond(200, { foo: "bar" });
+            const prom = client!.getTerms(SERVICE_TYPES.IM, "http://im.server");
+            await httpBackend!.flushAllExpected();
+            await expect(prom).resolves.toEqual({ foo: "bar" });
+        });
+    });
+
+    describe("publicRooms", () => {
+        it("should use GET request if no server or filter is specified", () => {
+            httpBackend!.when("GET", "/publicRooms").respond(200, {});
+            client!.publicRooms({});
+            return httpBackend!.flushAllExpected();
+        });
+
+        it("should use GET request if only server is specified", () => {
+            httpBackend!.when("GET", "/publicRooms").check(request => {
+                expect(request.queryParams.server).toBe("server1");
+            }).respond(200, {});
+            client!.publicRooms({ server: "server1" });
+            return httpBackend!.flushAllExpected();
+        });
+
+        it("should use POST request if filter is specified", () => {
+            httpBackend!.when("POST", "/publicRooms").check(request => {
+                expect(request.data.filter.generic_search_term).toBe("foobar");
+            }).respond(200, {});
+            client!.publicRooms({ filter: { generic_search_term: "foobar" } });
+            return httpBackend!.flushAllExpected();
+        });
+    });
+
+    describe("login", () => {
+        it("should persist values to the client opts", async () => {
+            const token = "!token&";
+            const userId = "@m:t";
+
+            httpBackend!.when("POST", "/login").respond(200, {
+                access_token: token,
+                user_id: userId,
+            });
+            const prom = client!.login("fake.login", {});
+            await httpBackend!.flushAllExpected();
+            const resp = await prom;
+            expect(resp.access_token).toBe(token);
+            expect(resp.user_id).toBe(userId);
+            expect(client.getUserId()).toBe(userId);
+            expect(client.http.opts.accessToken).toBe(token);
+        });
+    });
 });
 
-function withThreadId(event, newThreadId) {
+function withThreadId(event: MatrixEvent, newThreadId: string): MatrixEvent {
     const ret = event.toSnapshot();
     ret.setThreadId(newThreadId);
     return ret;
 }
 
-const buildEventMessageInThread = (root) => new MatrixEvent({
+const buildEventMessageInThread = (root: MatrixEvent) => new MatrixEvent({
     "age": 80098509,
     "content": {
         "algorithm": "m.megolm.v1.aes-sha2",
@@ -1233,7 +1351,7 @@ const buildEventPollResponseReference = () => new MatrixEvent({
     "user_id": "@andybalaam-test1:matrix.org",
 });
 
-const buildEventReaction = (event) => new MatrixEvent({
+const buildEventReaction = (event: MatrixEvent) => new MatrixEvent({
     "content": {
         "m.relates_to": {
             "event_id": event.getId(),
@@ -1252,7 +1370,7 @@ const buildEventReaction = (event) => new MatrixEvent({
     "room_id": "!STrMRsukXHtqQdSeHa:matrix.org",
 });
 
-const buildEventRedaction = (event) => new MatrixEvent({
+const buildEventRedaction = (event: MatrixEvent) => new MatrixEvent({
     "content": {
 
     },
@@ -1286,7 +1404,7 @@ const buildEventPollStartThreadRoot = () => new MatrixEvent({
     "user_id": "@andybalaam-test1:matrix.org",
 });
 
-const buildEventReply = (target) => new MatrixEvent({
+const buildEventReply = (target: MatrixEvent) => new MatrixEvent({
     "age": 80098509,
     "content": {
         "algorithm": "m.megolm.v1.aes-sha2",
@@ -1452,7 +1570,7 @@ const buildEventCreate = () => new MatrixEvent({
     "user_id": "@andybalaam-test1:matrix.org",
 });
 
-function assertObjectContains(obj, expected) {
+function assertObjectContains(obj: object, expected: any): void {
     for (const k in expected) {
         if (expected.hasOwnProperty(k)) {
             expect(obj[k]).toEqual(expected[k]);
diff --git a/spec/integ/matrix-client-opts.spec.ts b/spec/integ/matrix-client-opts.spec.ts
index 71403007464..5ea4fba7718 100644
--- a/spec/integ/matrix-client-opts.spec.ts
+++ b/spec/integ/matrix-client-opts.spec.ts
@@ -5,7 +5,6 @@ import { MatrixClient } from "../../src/matrix";
 import { MatrixScheduler } from "../../src/scheduler";
 import { MemoryStore } from "../../src/store/memory";
 import { MatrixError } from "../../src/http-api";
-import { ICreateClientOpts } from "../../src/client";
 import { IStore } from "../../src/store";
 
 describe("MatrixClient opts", function() {
@@ -69,7 +68,7 @@ describe("MatrixClient opts", function() {
         let client;
         beforeEach(function() {
             client = new MatrixClient({
-                request: httpBackend.requestFn as unknown as ICreateClientOpts['request'],
+                fetchFn: httpBackend.fetchFn as typeof global.fetch,
                 store: undefined,
                 baseUrl: baseUrl,
                 userId: userId,
@@ -129,7 +128,7 @@ describe("MatrixClient opts", function() {
         let client;
         beforeEach(function() {
             client = new MatrixClient({
-                request: httpBackend.requestFn as unknown as ICreateClientOpts['request'],
+                fetchFn: httpBackend.fetchFn as typeof global.fetch,
                 store: new MemoryStore() as IStore,
                 baseUrl: baseUrl,
                 userId: userId,
@@ -143,7 +142,7 @@ describe("MatrixClient opts", function() {
         });
 
         it("shouldn't retry sending events", function(done) {
-            httpBackend.when("PUT", "/txn1").fail(500, new MatrixError({
+            httpBackend.when("PUT", "/txn1").respond(500, new MatrixError({
                 errcode: "M_SOMETHING",
                 error: "Ruh roh",
             }));
diff --git a/spec/integ/matrix-client-room-timeline.spec.ts b/spec/integ/matrix-client-room-timeline.spec.ts
index 48ecee32b4b..42d90d91c73 100644
--- a/spec/integ/matrix-client-room-timeline.spec.ts
+++ b/spec/integ/matrix-client-room-timeline.spec.ts
@@ -18,7 +18,7 @@ import HttpBackend from "matrix-mock-request";
 
 import * as utils from "../test-utils/test-utils";
 import { EventStatus } from "../../src/models/event";
-import { ClientEvent, IEvent, MatrixClient, RoomEvent } from "../../src";
+import { MatrixError, ClientEvent, IEvent, MatrixClient, RoomEvent } from "../../src";
 import { TestClient } from "../TestClient";
 
 describe("MatrixClient room timelines", function() {
@@ -802,17 +802,14 @@ describe("MatrixClient room timelines", function() {
         it('Timeline recovers after `/context` request to generate new timeline fails', async () => {
             // `/context` request for `refreshLiveTimeline()` -> `getEventTimeline()`
             // to construct a new timeline from.
-            httpBackend!.when("GET", contextUrl)
-                .respond(500, function() {
-                    // The timeline should be cleared at this point in the refresh
-                    expect(room.timeline.length).toEqual(0);
-
-                    return {
-                        errcode: 'TEST_FAKE_ERROR',
-                        error: 'We purposely intercepted this /context request to make it fail ' +
-                                 'in order to test whether the refresh timeline code is resilient',
-                    };
-                });
+            httpBackend!.when("GET", contextUrl).check(() => {
+                // The timeline should be cleared at this point in the refresh
+                expect(room.timeline.length).toEqual(0);
+            }).respond(500, new MatrixError({
+                errcode: 'TEST_FAKE_ERROR',
+                error: 'We purposely intercepted this /context request to make it fail ' +
+                    'in order to test whether the refresh timeline code is resilient',
+            }));
 
             // Refresh the timeline and expect it to fail
             const settledFailedRefreshPromises = await Promise.allSettled([
diff --git a/spec/integ/matrix-client-syncing.spec.ts b/spec/integ/matrix-client-syncing.spec.ts
index 78795051cc8..fd8fd7b7d18 100644
--- a/spec/integ/matrix-client-syncing.spec.ts
+++ b/spec/integ/matrix-client-syncing.spec.ts
@@ -1572,7 +1572,7 @@ describe("MatrixClient syncing (IndexedDB version)", () => {
         const idbHttpBackend = idbTestClient.httpBackend;
         const idbClient = idbTestClient.client;
         idbHttpBackend.when("GET", "/versions").respond(200, {});
-        idbHttpBackend.when("GET", "/pushrules").respond(200, {});
+        idbHttpBackend.when("GET", "/pushrules/").respond(200, {});
         idbHttpBackend.when("POST", "/filter").respond(200, { filter_id: "a filter id" });
 
         await idbClient.initCrypto();
diff --git a/spec/integ/sliding-sync-sdk.spec.ts b/spec/integ/sliding-sync-sdk.spec.ts
index 47e6ba8dfb0..3e50064a6d3 100644
--- a/spec/integ/sliding-sync-sdk.spec.ts
+++ b/spec/integ/sliding-sync-sdk.spec.ts
@@ -23,12 +23,13 @@ import { TestClient } from "../TestClient";
 import { IRoomEvent, IStateEvent } from "../../src/sync-accumulator";
 import {
     MatrixClient, MatrixEvent, NotificationCountType, JoinRule, MatrixError,
-    EventType, IPushRules, PushRuleKind, TweakName, ClientEvent,
+    EventType, IPushRules, PushRuleKind, TweakName, ClientEvent, RoomMemberEvent,
 } from "../../src";
 import { SlidingSyncSdk } from "../../src/sliding-sync-sdk";
 import { SyncState } from "../../src/sync";
 import { IStoredClientOpts } from "../../src/client";
 import { logger } from "../../src/logger";
+import { emitPromise } from "../test-utils/test-utils";
 
 describe("SlidingSyncSdk", () => {
     let client: MatrixClient | undefined;
@@ -530,6 +531,7 @@ describe("SlidingSyncSdk", () => {
                 ],
             });
             await httpBackend!.flush("/profile", 1, 1000);
+            await emitPromise(client!, RoomMemberEvent.Name);
             const room = client!.getRoom(roomId)!;
             expect(room).toBeDefined();
             const inviteeMember = room.getMember(invitee)!;
diff --git a/spec/setupTests.ts b/spec/setupTests.ts
new file mode 100644
index 00000000000..bbd70fe3d97
--- /dev/null
+++ b/spec/setupTests.ts
@@ -0,0 +1,19 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import DOMException from "domexception";
+
+global.DOMException = DOMException;
diff --git a/spec/unit/autodiscovery.spec.ts b/spec/unit/autodiscovery.spec.ts
index 939f477977a..13688c25b25 100644
--- a/spec/unit/autodiscovery.spec.ts
+++ b/spec/unit/autodiscovery.spec.ts
@@ -17,13 +17,12 @@ limitations under the License.
 
 import MockHttpBackend from "matrix-mock-request";
 
-import { request } from "../../src/matrix";
 import { AutoDiscovery } from "../../src/autodiscovery";
 
 describe("AutoDiscovery", function() {
     const getHttpBackend = (): MockHttpBackend => {
         const httpBackend = new MockHttpBackend();
-        request(httpBackend.requestFn);
+        AutoDiscovery.setFetchFn(httpBackend.fetchFn as typeof global.fetch);
         return httpBackend;
     };
 
@@ -176,8 +175,7 @@ describe("AutoDiscovery", function() {
         ]);
     });
 
-    it("should return FAIL_PROMPT when .well-known does not have a base_url for " +
-        "m.homeserver (empty string)", function() {
+    it("should return FAIL_PROMPT when .well-known does not have a base_url for m.homeserver (empty string)", () => {
         const httpBackend = getHttpBackend();
         httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
             "m.homeserver": {
@@ -205,8 +203,7 @@ describe("AutoDiscovery", function() {
         ]);
     });
 
-    it("should return FAIL_PROMPT when .well-known does not have a base_url for " +
-        "m.homeserver (no property)", function() {
+    it("should return FAIL_PROMPT when .well-known does not have a base_url for m.homeserver (no property)", () => {
         const httpBackend = getHttpBackend();
         httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
             "m.homeserver": {},
@@ -232,8 +229,7 @@ describe("AutoDiscovery", function() {
         ]);
     });
 
-    it("should return FAIL_ERROR when .well-known has an invalid base_url for " +
-        "m.homeserver (disallowed scheme)", function() {
+    it("should return FAIL_ERROR when .well-known has an invalid base_url for m.homeserver (disallowed scheme)", () => {
         const httpBackend = getHttpBackend();
         httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
             "m.homeserver": {
@@ -679,4 +675,76 @@ describe("AutoDiscovery", function() {
             }),
         ]);
     });
+
+    it("should return FAIL_PROMPT for connection errors", () => {
+        const httpBackend = getHttpBackend();
+        httpBackend.when("GET", "/.well-known/matrix/client").fail(0, undefined);
+        return Promise.all([
+            httpBackend.flushAllExpected(),
+            AutoDiscovery.findClientConfig("example.org").then((conf) => {
+                const expected = {
+                    "m.homeserver": {
+                        state: "FAIL_PROMPT",
+                        error: AutoDiscovery.ERROR_INVALID,
+                        base_url: null,
+                    },
+                    "m.identity_server": {
+                        state: "PROMPT",
+                        error: null,
+                        base_url: null,
+                    },
+                };
+
+                expect(conf).toEqual(expected);
+            }),
+        ]);
+    });
+
+    it("should return FAIL_PROMPT for fetch errors", () => {
+        const httpBackend = getHttpBackend();
+        httpBackend.when("GET", "/.well-known/matrix/client").fail(0, new Error("CORS or something"));
+        return Promise.all([
+            httpBackend.flushAllExpected(),
+            AutoDiscovery.findClientConfig("example.org").then((conf) => {
+                const expected = {
+                    "m.homeserver": {
+                        state: "FAIL_PROMPT",
+                        error: AutoDiscovery.ERROR_INVALID,
+                        base_url: null,
+                    },
+                    "m.identity_server": {
+                        state: "PROMPT",
+                        error: null,
+                        base_url: null,
+                    },
+                };
+
+                expect(conf).toEqual(expected);
+            }),
+        ]);
+    });
+
+    it("should return FAIL_PROMPT for invalid JSON", () => {
+        const httpBackend = getHttpBackend();
+        httpBackend.when("GET", "/.well-known/matrix/client").respond(200, "<html>", true);
+        return Promise.all([
+            httpBackend.flushAllExpected(),
+            AutoDiscovery.findClientConfig("example.org").then((conf) => {
+                const expected = {
+                    "m.homeserver": {
+                        state: "FAIL_PROMPT",
+                        error: AutoDiscovery.ERROR_INVALID,
+                        base_url: null,
+                    },
+                    "m.identity_server": {
+                        state: "PROMPT",
+                        error: null,
+                        base_url: null,
+                    },
+                };
+
+                expect(conf).toEqual(expected);
+            }),
+        ]);
+    });
 });
diff --git a/spec/unit/crypto/backup.spec.ts b/spec/unit/crypto/backup.spec.ts
index acec47fcee2..ca4c09c532c 100644
--- a/spec/unit/crypto/backup.spec.ts
+++ b/spec/unit/crypto/backup.spec.ts
@@ -30,7 +30,7 @@ import { Crypto } from "../../../src/crypto";
 import { resetCrossSigningKeys } from "./crypto-utils";
 import { BackupManager } from "../../../src/crypto/backup";
 import { StubStore } from "../../../src/store/stub";
-import { IAbortablePromise, MatrixScheduler } from '../../../src';
+import { MatrixScheduler } from '../../../src';
 
 const Olm = global.Olm;
 
@@ -131,7 +131,7 @@ function makeTestClient(cryptoStore) {
         baseUrl: "https://my.home.server",
         idBaseUrl: "https://identity.server",
         accessToken: "my.access.token",
-        request: jest.fn(), // NOP
+        fetchFn: jest.fn(), // NOP
         store: store,
         scheduler: scheduler,
         userId: "@alice:bar",
@@ -197,7 +197,7 @@ describe("MegolmBackup", function() {
             // to tick the clock between the first try and the retry.
             const realSetTimeout = global.setTimeout;
             jest.spyOn(global, 'setTimeout').mockImplementation(function(f, n) {
-                return realSetTimeout(f, n/100);
+                return realSetTimeout(f!, n/100);
             });
         });
 
@@ -298,25 +298,25 @@ describe("MegolmBackup", function() {
                     });
                     let numCalls = 0;
                     return new Promise<void>((resolve, reject) => {
-                        client.http.authedRequest = function(
-                            callback, method, path, queryParams, data, opts,
-                        ) {
+                        client.http.authedRequest = function<T>(
+                            method, path, queryParams, data, opts,
+                        ): Promise<T> {
                             ++numCalls;
                             expect(numCalls).toBeLessThanOrEqual(1);
                             if (numCalls >= 2) {
                                 // exit out of retry loop if there's something wrong
                                 reject(new Error("authedRequest called too many timmes"));
-                                return Promise.resolve({}) as IAbortablePromise<any>;
+                                return Promise.resolve({} as T);
                             }
                             expect(method).toBe("PUT");
                             expect(path).toBe("/room_keys/keys");
                             expect(queryParams.version).toBe('1');
-                            expect(data.rooms[ROOM_ID].sessions).toBeDefined();
-                            expect(data.rooms[ROOM_ID].sessions).toHaveProperty(
+                            expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toBeDefined();
+                            expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toHaveProperty(
                                 groupSession.session_id(),
                             );
                             resolve();
-                            return Promise.resolve({}) as IAbortablePromise<any>;
+                            return Promise.resolve({} as T);
                         };
                         client.crypto.backupManager.backupGroupSession(
                             "F0Q2NmyJNgUVj9DGsb4ZQt3aVxhVcUQhg7+gvW0oyKI",
@@ -381,25 +381,25 @@ describe("MegolmBackup", function() {
                     });
                     let numCalls = 0;
                     return new Promise<void>((resolve, reject) => {
-                        client.http.authedRequest = function(
-                            callback, method, path, queryParams, data, opts,
-                        ) {
+                        client.http.authedRequest = function<T>(
+                            method, path, queryParams, data, opts,
+                        ): Promise<T> {
                             ++numCalls;
                             expect(numCalls).toBeLessThanOrEqual(1);
                             if (numCalls >= 2) {
                                 // exit out of retry loop if there's something wrong
                                 reject(new Error("authedRequest called too many timmes"));
-                                return Promise.resolve({}) as IAbortablePromise<any>;
+                                return Promise.resolve({} as T);
                             }
                             expect(method).toBe("PUT");
                             expect(path).toBe("/room_keys/keys");
                             expect(queryParams.version).toBe('1');
-                            expect(data.rooms[ROOM_ID].sessions).toBeDefined();
-                            expect(data.rooms[ROOM_ID].sessions).toHaveProperty(
+                            expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toBeDefined();
+                            expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toHaveProperty(
                                 groupSession.session_id(),
                             );
                             resolve();
-                            return Promise.resolve({}) as IAbortablePromise<any>;
+                            return Promise.resolve({} as T);
                         };
                         client.crypto.backupManager.backupGroupSession(
                             "F0Q2NmyJNgUVj9DGsb4ZQt3aVxhVcUQhg7+gvW0oyKI",
@@ -439,7 +439,7 @@ describe("MegolmBackup", function() {
                 new Promise<void>((resolve, reject) => {
                     let backupInfo;
                     client.http.authedRequest = function(
-                        callback, method, path, queryParams, data, opts,
+                        method, path, queryParams, data, opts,
                     ) {
                         ++numCalls;
                         expect(numCalls).toBeLessThanOrEqual(2);
@@ -449,23 +449,23 @@ describe("MegolmBackup", function() {
                             try {
                                 // make sure auth_data is signed by the master key
                                 olmlib.pkVerify(
-                                    data.auth_data, client.getCrossSigningId(), "@alice:bar",
+                                    (data as Record<string, any>).auth_data, client.getCrossSigningId(), "@alice:bar",
                                 );
                             } catch (e) {
                                 reject(e);
-                                return Promise.resolve({}) as IAbortablePromise<any>;
+                                return Promise.resolve({});
                             }
                             backupInfo = data;
-                            return Promise.resolve({}) as IAbortablePromise<any>;
+                            return Promise.resolve({});
                         } else if (numCalls === 2) {
                             expect(method).toBe("GET");
                             expect(path).toBe("/room_keys/version");
                             resolve();
-                            return Promise.resolve(backupInfo) as IAbortablePromise<any>;
+                            return Promise.resolve(backupInfo);
                         } else {
                             // exit out of retry loop if there's something wrong
                             reject(new Error("authedRequest called too many times"));
-                            return Promise.resolve({}) as IAbortablePromise<any>;
+                            return Promise.resolve({});
                         }
                     };
                 }),
@@ -495,7 +495,7 @@ describe("MegolmBackup", function() {
                 baseUrl: "https://my.home.server",
                 idBaseUrl: "https://identity.server",
                 accessToken: "my.access.token",
-                request: jest.fn(), // NOP
+                fetchFn: jest.fn(), // NOP
                 store: store,
                 scheduler: scheduler,
                 userId: "@alice:bar",
@@ -542,30 +542,30 @@ describe("MegolmBackup", function() {
             let numCalls = 0;
 
             await new Promise<void>((resolve, reject) => {
-                client.http.authedRequest = function(
-                    callback, method, path, queryParams, data, opts,
-                ) {
+                client.http.authedRequest = function<T>(
+                    method, path, queryParams, data, opts,
+                ): Promise<T> {
                     ++numCalls;
                     expect(numCalls).toBeLessThanOrEqual(2);
                     if (numCalls >= 3) {
                         // exit out of retry loop if there's something wrong
                         reject(new Error("authedRequest called too many timmes"));
-                        return Promise.resolve({}) as IAbortablePromise<any>;
+                        return Promise.resolve({} as T);
                     }
                     expect(method).toBe("PUT");
                     expect(path).toBe("/room_keys/keys");
                     expect(queryParams.version).toBe('1');
-                    expect(data.rooms[ROOM_ID].sessions).toBeDefined();
-                    expect(data.rooms[ROOM_ID].sessions).toHaveProperty(
+                    expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toBeDefined();
+                    expect((data as Record<string, any>).rooms[ROOM_ID].sessions).toHaveProperty(
                         groupSession.session_id(),
                     );
                     if (numCalls > 1) {
                         resolve();
-                        return Promise.resolve({}) as IAbortablePromise<any>;
+                        return Promise.resolve({} as T);
                     } else {
                         return Promise.reject(
                             new Error("this is an expected failure"),
-                        ) as IAbortablePromise<any>;
+                        );
                     }
                 };
                 return client.crypto.backupManager.backupGroupSession(
diff --git a/spec/unit/crypto/cross-signing.spec.ts b/spec/unit/crypto/cross-signing.spec.ts
index 30c1bf82ce3..bfa7625cbe8 100644
--- a/spec/unit/crypto/cross-signing.spec.ts
+++ b/spec/unit/crypto/cross-signing.spec.ts
@@ -141,7 +141,7 @@ describe("Cross Signing", function() {
         };
         alice.uploadKeySignatures = async () => ({ failures: {} });
         alice.setAccountData = async () => ({});
-        alice.getAccountDataFromServer = async <T extends {[k: string]: any}>(): Promise<T> => ({} as T);
+        alice.getAccountDataFromServer = async <T extends {[k: string]: any}>(): Promise<T | null> => ({} as T);
         const authUploadDeviceSigningKeys = async func => await func({});
 
         // Try bootstrap, expecting `authUploadDeviceSigningKeys` to pass
diff --git a/spec/unit/crypto/secrets.spec.ts b/spec/unit/crypto/secrets.spec.ts
index d6ae8c3a363..7692292fff2 100644
--- a/spec/unit/crypto/secrets.spec.ts
+++ b/spec/unit/crypto/secrets.spec.ts
@@ -109,16 +109,13 @@ describe("Secrets", function() {
         const secretStorage = alice.crypto.secretStorage;
 
         jest.spyOn(alice, 'setAccountData').mockImplementation(
-            async function(eventType, contents, callback) {
+            async function(eventType, contents) {
                 alice.store.storeAccountDataEvents([
                     new MatrixEvent({
                         type: eventType,
                         content: contents,
                     }),
                 ]);
-                if (callback) {
-                    callback(undefined, undefined);
-                }
                 return {};
             });
 
@@ -192,7 +189,7 @@ describe("Secrets", function() {
                 },
             },
         );
-        alice.setAccountData = async function(eventType, contents, callback) {
+        alice.setAccountData = async function(eventType, contents) {
             alice.store.storeAccountDataEvents([
                 new MatrixEvent({
                     type: eventType,
@@ -332,7 +329,7 @@ describe("Secrets", function() {
             );
             bob.uploadDeviceSigningKeys = async () => ({});
             bob.uploadKeySignatures = jest.fn().mockResolvedValue(undefined);
-            bob.setAccountData = async function(eventType, contents, callback) {
+            bob.setAccountData = async function(eventType, contents) {
                 const event = new MatrixEvent({
                     type: eventType,
                     content: contents,
diff --git a/spec/unit/event-mapper.spec.ts b/spec/unit/event-mapper.spec.ts
index a444c34fb0c..c21348c80e4 100644
--- a/spec/unit/event-mapper.spec.ts
+++ b/spec/unit/event-mapper.spec.ts
@@ -29,7 +29,7 @@ describe("eventMapperFor", function() {
         client = new MatrixClient({
             baseUrl: "https://my.home.server",
             accessToken: "my.access.token",
-            request: function() {} as any, // NOP
+            fetchFn: function() {} as any, // NOP
             store: {
                 getRoom(roomId: string): Room | null {
                     return rooms.find(r => r.roomId === roomId);
diff --git a/spec/unit/http-api/__snapshots__/index.spec.ts.snap b/spec/unit/http-api/__snapshots__/index.spec.ts.snap
new file mode 100644
index 00000000000..e6487ddeb0f
--- /dev/null
+++ b/spec/unit/http-api/__snapshots__/index.spec.ts.snap
@@ -0,0 +1,11 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`MatrixHttpApi should return expected object from \`getContentUri\` 1`] = `
+{
+  "base": "http://baseUrl",
+  "params": {
+    "access_token": "token",
+  },
+  "path": "/_matrix/media/r0/upload",
+}
+`;
diff --git a/spec/unit/http-api/fetch.spec.ts b/spec/unit/http-api/fetch.spec.ts
new file mode 100644
index 00000000000..e100f2d9387
--- /dev/null
+++ b/spec/unit/http-api/fetch.spec.ts
@@ -0,0 +1,223 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { FetchHttpApi } from "../../../src/http-api/fetch";
+import { TypedEventEmitter } from "../../../src/models/typed-event-emitter";
+import { ClientPrefix, HttpApiEvent, HttpApiEventHandlerMap, IdentityPrefix, IHttpOpts, Method } from "../../../src";
+import { emitPromise } from "../../test-utils/test-utils";
+
+describe("FetchHttpApi", () => {
+    const baseUrl = "http://baseUrl";
+    const idBaseUrl = "http://idBaseUrl";
+    const prefix = ClientPrefix.V3;
+
+    it("should support aborting multiple times", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn });
+
+        api.request(Method.Get, "/foo");
+        api.request(Method.Get, "/baz");
+        expect(fetchFn.mock.calls[0][0].href.endsWith("/foo")).toBeTruthy();
+        expect(fetchFn.mock.calls[0][1].signal.aborted).toBeFalsy();
+        expect(fetchFn.mock.calls[1][0].href.endsWith("/baz")).toBeTruthy();
+        expect(fetchFn.mock.calls[1][1].signal.aborted).toBeFalsy();
+
+        api.abort();
+        expect(fetchFn.mock.calls[0][1].signal.aborted).toBeTruthy();
+        expect(fetchFn.mock.calls[1][1].signal.aborted).toBeTruthy();
+
+        api.request(Method.Get, "/bar");
+        expect(fetchFn.mock.calls[2][0].href.endsWith("/bar")).toBeTruthy();
+        expect(fetchFn.mock.calls[2][1].signal.aborted).toBeFalsy();
+
+        api.abort();
+        expect(fetchFn.mock.calls[2][1].signal.aborted).toBeTruthy();
+    });
+
+    it("should fall back to global fetch if fetchFn not provided", () => {
+        global.fetch = jest.fn();
+        expect(global.fetch).not.toHaveBeenCalled();
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        api.fetch("test");
+        expect(global.fetch).toHaveBeenCalled();
+    });
+
+    it("should update identity server base url", () => {
+        const api = new FetchHttpApi<IHttpOpts>(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        expect(api.opts.idBaseUrl).toBeUndefined();
+        api.setIdBaseUrl("https://id.foo.bar");
+        expect(api.opts.idBaseUrl).toBe("https://id.foo.bar");
+    });
+
+    describe("idServerRequest", () => {
+        it("should throw if no idBaseUrl", () => {
+            const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+            expect(() => api.idServerRequest(Method.Get, "/test", {}, IdentityPrefix.V2))
+                .toThrow("No identity server base URL set");
+        });
+
+        it("should send params as query string for GET requests", () => {
+            const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+            const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, idBaseUrl, prefix, fetchFn });
+            api.idServerRequest(Method.Get, "/test", { foo: "bar", via: ["a", "b"] }, IdentityPrefix.V2);
+            expect(fetchFn.mock.calls[0][0].searchParams.get("foo")).toBe("bar");
+            expect(fetchFn.mock.calls[0][0].searchParams.getAll("via")).toEqual(["a", "b"]);
+        });
+
+        it("should send params as body for non-GET requests", () => {
+            const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+            const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, idBaseUrl, prefix, fetchFn });
+            const params = { foo: "bar", via: ["a", "b"] };
+            api.idServerRequest(Method.Post, "/test", params, IdentityPrefix.V2);
+            expect(fetchFn.mock.calls[0][0].searchParams.get("foo")).not.toBe("bar");
+            expect(JSON.parse(fetchFn.mock.calls[0][1].body)).toStrictEqual(params);
+        });
+
+        it("should add Authorization header if token provided", () => {
+            const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+            const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, idBaseUrl, prefix, fetchFn });
+            api.idServerRequest(Method.Post, "/test", {}, IdentityPrefix.V2, "token");
+            expect(fetchFn.mock.calls[0][1].headers.Authorization).toBe("Bearer token");
+        });
+    });
+
+    it("should return the Response object if onlyData=false", async () => {
+        const res = { ok: true };
+        const fetchFn = jest.fn().mockResolvedValue(res);
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn, onlyData: false });
+        await expect(api.requestOtherUrl(Method.Get, "http://url")).resolves.toBe(res);
+    });
+
+    it("should return text if json=false", async () => {
+        const text = "418 I'm a teapot";
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true, text: jest.fn().mockResolvedValue(text) });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn, onlyData: true });
+        await expect(api.requestOtherUrl(Method.Get, "http://url", undefined, {
+            json: false,
+        })).resolves.toBe(text);
+    });
+
+    it("should send token via query params if useAuthorizationHeader=false", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+            useAuthorizationHeader: false,
+        });
+        api.authedRequest(Method.Get, "/path");
+        expect(fetchFn.mock.calls[0][0].searchParams.get("access_token")).toBe("token");
+    });
+
+    it("should send token via headers by default", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+        });
+        api.authedRequest(Method.Get, "/path");
+        expect(fetchFn.mock.calls[0][1].headers["Authorization"]).toBe("Bearer token");
+    });
+
+    it("should not send a token if not calling `authedRequest`", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+        });
+        api.request(Method.Get, "/path");
+        expect(fetchFn.mock.calls[0][0].searchParams.get("access_token")).toBeFalsy();
+        expect(fetchFn.mock.calls[0][1].headers["Authorization"]).toBeFalsy();
+    });
+
+    it("should ensure no token is leaked out via query params if sending via headers", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+            useAuthorizationHeader: true,
+        });
+        api.authedRequest(Method.Get, "/path", { access_token: "123" });
+        expect(fetchFn.mock.calls[0][0].searchParams.get("access_token")).toBeFalsy();
+        expect(fetchFn.mock.calls[0][1].headers["Authorization"]).toBe("Bearer token");
+    });
+
+    it("should not override manually specified access token via query params", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+            useAuthorizationHeader: false,
+        });
+        api.authedRequest(Method.Get, "/path", { access_token: "RealToken" });
+        expect(fetchFn.mock.calls[0][0].searchParams.get("access_token")).toBe("RealToken");
+    });
+
+    it("should not override manually specified access token via header", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            accessToken: "token",
+            useAuthorizationHeader: true,
+        });
+        api.authedRequest(Method.Get, "/path", undefined, undefined, {
+            headers: { Authorization: "Bearer RealToken" },
+        });
+        expect(fetchFn.mock.calls[0][1].headers["Authorization"]).toBe("Bearer RealToken");
+    });
+
+    it("should not override Accept header", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn });
+        api.authedRequest(Method.Get, "/path", undefined, undefined, {
+            headers: { Accept: "text/html" },
+        });
+        expect(fetchFn.mock.calls[0][1].headers["Accept"]).toBe("text/html");
+    });
+
+    it("should emit NoConsent when given errcode=M_CONTENT_NOT_GIVEN", async () => {
+        const fetchFn = jest.fn().mockResolvedValue({
+            ok: false,
+            headers: {
+                get(name: string): string | null {
+                    return name === "Content-Type" ? "application/json" : null;
+                },
+            },
+            text: jest.fn().mockResolvedValue(JSON.stringify({
+                errcode: "M_CONSENT_NOT_GIVEN",
+                error: "Ye shall ask for consent",
+            })),
+        });
+        const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
+        const api = new FetchHttpApi(emitter, { baseUrl, prefix, fetchFn });
+
+        await Promise.all([
+            emitPromise(emitter, HttpApiEvent.NoConsent),
+            expect(api.authedRequest(Method.Get, "/path")).rejects.toThrow("Ye shall ask for consent"),
+        ]);
+    });
+});
diff --git a/spec/unit/http-api/index.spec.ts b/spec/unit/http-api/index.spec.ts
new file mode 100644
index 00000000000..89e122452f6
--- /dev/null
+++ b/spec/unit/http-api/index.spec.ts
@@ -0,0 +1,228 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import DOMException from "domexception";
+import { mocked } from "jest-mock";
+
+import { ClientPrefix, MatrixHttpApi, Method, UploadResponse } from "../../../src";
+import { TypedEventEmitter } from "../../../src/models/typed-event-emitter";
+
+type Writeable<T> = { -readonly [P in keyof T]: T[P] };
+
+jest.useFakeTimers();
+
+describe("MatrixHttpApi", () => {
+    const baseUrl = "http://baseUrl";
+    const prefix = ClientPrefix.V3;
+
+    let xhr: Partial<Writeable<XMLHttpRequest>>;
+    let upload: Promise<UploadResponse>;
+
+    const DONE = 0;
+
+    global.DOMException = DOMException;
+
+    beforeEach(() => {
+        xhr = {
+            upload: {} as XMLHttpRequestUpload,
+            open: jest.fn(),
+            send: jest.fn(),
+            abort: jest.fn(),
+            setRequestHeader: jest.fn(),
+            onreadystatechange: undefined,
+            getResponseHeader: jest.fn(),
+        };
+        // We stub out XHR here as it is not available in JSDOM
+        // @ts-ignore
+        global.XMLHttpRequest = jest.fn().mockReturnValue(xhr);
+        // @ts-ignore
+        global.XMLHttpRequest.DONE = DONE;
+    });
+
+    afterEach(() => {
+        upload?.catch(() => {});
+        // Abort any remaining requests
+        xhr.readyState = DONE;
+        xhr.status = 0;
+        // @ts-ignore
+        xhr.onreadystatechange?.(new Event("test"));
+    });
+
+    it("should fall back to `fetch` where xhr is unavailable", () => {
+        global.XMLHttpRequest = undefined;
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true, json: jest.fn().mockResolvedValue({}) });
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn });
+        upload = api.uploadContent({} as File);
+        expect(fetchFn).toHaveBeenCalled();
+    });
+
+    it("should prefer xhr where available", () => {
+        const fetchFn = jest.fn().mockResolvedValue({ ok: true });
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn });
+        upload = api.uploadContent({} as File);
+        expect(fetchFn).not.toHaveBeenCalled();
+        expect(xhr.open).toHaveBeenCalled();
+    });
+
+    it("should send access token in query params if header disabled", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            accessToken: "token",
+            useAuthorizationHeader: false,
+        });
+        upload = api.uploadContent({} as File);
+        expect(xhr.open)
+            .toHaveBeenCalledWith(Method.Post, baseUrl.toLowerCase() + "/_matrix/media/r0/upload?access_token=token");
+        expect(xhr.setRequestHeader).not.toHaveBeenCalledWith("Authorization");
+    });
+
+    it("should send access token in header by default", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            accessToken: "token",
+        });
+        upload = api.uploadContent({} as File);
+        expect(xhr.open).toHaveBeenCalledWith(Method.Post, baseUrl.toLowerCase() + "/_matrix/media/r0/upload");
+        expect(xhr.setRequestHeader).toHaveBeenCalledWith("Authorization", "Bearer token");
+    });
+
+    it("should include filename by default", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File, { name: "name" });
+        expect(xhr.open)
+            .toHaveBeenCalledWith(Method.Post, baseUrl.toLowerCase() + "/_matrix/media/r0/upload?filename=name");
+    });
+
+    it("should allow not sending the filename", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File, { name: "name", includeFilename: false });
+        expect(xhr.open).toHaveBeenCalledWith(Method.Post, baseUrl.toLowerCase() + "/_matrix/media/r0/upload");
+    });
+
+    it("should abort xhr when the upload is aborted", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+        api.cancelUpload(upload);
+        expect(xhr.abort).toHaveBeenCalled();
+        return expect(upload).rejects.toThrow("Aborted");
+    });
+
+    it("should timeout if no progress in 30s", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+        jest.advanceTimersByTime(25000);
+        // @ts-ignore
+        xhr.upload.onprogress(new Event("progress", { loaded: 1, total: 100 }));
+        jest.advanceTimersByTime(25000);
+        expect(xhr.abort).not.toHaveBeenCalled();
+        jest.advanceTimersByTime(5000);
+        expect(xhr.abort).toHaveBeenCalled();
+    });
+
+    it("should call progressHandler", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        const progressHandler = jest.fn();
+        upload = api.uploadContent({} as File, { progressHandler });
+        const progressEvent = new Event("progress") as ProgressEvent;
+        Object.assign(progressEvent, { loaded: 1, total: 100 });
+        // @ts-ignore
+        xhr.upload.onprogress(progressEvent);
+        expect(progressHandler).toHaveBeenCalledWith({ loaded: 1, total: 100 });
+
+        Object.assign(progressEvent, { loaded: 95, total: 100 });
+        // @ts-ignore
+        xhr.upload.onprogress(progressEvent);
+        expect(progressHandler).toHaveBeenCalledWith({ loaded: 95, total: 100 });
+    });
+
+    it("should error when no response body", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+
+        xhr.readyState = DONE;
+        xhr.responseText = "";
+        xhr.status = 200;
+        // @ts-ignore
+        xhr.onreadystatechange?.(new Event("test"));
+
+        return expect(upload).rejects.toThrow("No response body.");
+    });
+
+    it("should error on a 400-code", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+
+        xhr.readyState = DONE;
+        xhr.responseText = '{"errcode": "M_NOT_FOUND", "error": "Not found"}';
+        xhr.status = 404;
+        mocked(xhr.getResponseHeader).mockReturnValue("application/json");
+        // @ts-ignore
+        xhr.onreadystatechange?.(new Event("test"));
+
+        return expect(upload).rejects.toThrow("Not found");
+    });
+
+    it("should return response on successful upload", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+
+        xhr.readyState = DONE;
+        xhr.responseText = '{"content_uri": "mxc://server/foobar"}';
+        xhr.status = 200;
+        mocked(xhr.getResponseHeader).mockReturnValue("application/json");
+        // @ts-ignore
+        xhr.onreadystatechange?.(new Event("test"));
+
+        return expect(upload).resolves.toStrictEqual({ content_uri: "mxc://server/foobar" });
+    });
+
+    it("should abort xhr when calling `cancelUpload`", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+        expect(api.cancelUpload(upload)).toBeTruthy();
+        expect(xhr.abort).toHaveBeenCalled();
+    });
+
+    it("should return false when `cancelUpload` is called but unsuccessful", async () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+
+        xhr.readyState = DONE;
+        xhr.status = 500;
+        mocked(xhr.getResponseHeader).mockReturnValue("application/json");
+        // @ts-ignore
+        xhr.onreadystatechange?.(new Event("test"));
+        await upload.catch(() => {});
+
+        expect(api.cancelUpload(upload)).toBeFalsy();
+        expect(xhr.abort).not.toHaveBeenCalled();
+    });
+
+    it("should return active uploads in `getCurrentUploads`", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix });
+        upload = api.uploadContent({} as File);
+        expect(api.getCurrentUploads().find(u => u.promise === upload)).toBeTruthy();
+        api.cancelUpload(upload);
+        expect(api.getCurrentUploads().find(u => u.promise === upload)).toBeFalsy();
+    });
+
+    it("should return expected object from `getContentUri`", () => {
+        const api = new MatrixHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, accessToken: "token" });
+        expect(api.getContentUri()).toMatchSnapshot();
+    });
+});
diff --git a/spec/unit/http-api/utils.spec.ts b/spec/unit/http-api/utils.spec.ts
new file mode 100644
index 00000000000..1a266c8423c
--- /dev/null
+++ b/spec/unit/http-api/utils.spec.ts
@@ -0,0 +1,183 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { mocked } from "jest-mock";
+
+import {
+    anySignal,
+    ConnectionError,
+    MatrixError,
+    parseErrorResponse,
+    retryNetworkOperation,
+    timeoutSignal,
+} from "../../../src";
+import { sleep } from "../../../src/utils";
+
+jest.mock("../../../src/utils");
+
+describe("timeoutSignal", () => {
+    jest.useFakeTimers();
+
+    it("should fire abort signal after specified timeout", () => {
+        const signal = timeoutSignal(3000);
+        const onabort = jest.fn();
+        signal.onabort = onabort;
+        expect(signal.aborted).toBeFalsy();
+        expect(onabort).not.toHaveBeenCalled();
+
+        jest.advanceTimersByTime(3000);
+        expect(signal.aborted).toBeTruthy();
+        expect(onabort).toHaveBeenCalled();
+    });
+});
+
+describe("anySignal", () => {
+    jest.useFakeTimers();
+
+    it("should fire when any signal fires", () => {
+        const { signal } = anySignal([
+            timeoutSignal(3000),
+            timeoutSignal(2000),
+        ]);
+
+        const onabort = jest.fn();
+        signal.onabort = onabort;
+        expect(signal.aborted).toBeFalsy();
+        expect(onabort).not.toHaveBeenCalled();
+
+        jest.advanceTimersByTime(2000);
+        expect(signal.aborted).toBeTruthy();
+        expect(onabort).toHaveBeenCalled();
+    });
+
+    it("should cleanup when instructed", () => {
+        const { signal, cleanup } = anySignal([
+            timeoutSignal(3000),
+            timeoutSignal(2000),
+        ]);
+
+        const onabort = jest.fn();
+        signal.onabort = onabort;
+        expect(signal.aborted).toBeFalsy();
+        expect(onabort).not.toHaveBeenCalled();
+
+        cleanup();
+        jest.advanceTimersByTime(2000);
+        expect(signal.aborted).toBeFalsy();
+        expect(onabort).not.toHaveBeenCalled();
+    });
+
+    it("should abort immediately if passed an aborted signal", () => {
+        const controller = new AbortController();
+        controller.abort();
+        const { signal } = anySignal([controller.signal]);
+        expect(signal.aborted).toBeTruthy();
+    });
+});
+
+describe("parseErrorResponse", () => {
+    it("should resolve Matrix Errors from XHR", () => {
+        expect(parseErrorResponse({
+            getResponseHeader(name: string): string | null {
+                return name === "Content-Type" ? "application/json" : null;
+            },
+            status: 500,
+        } as XMLHttpRequest, '{"errcode": "TEST"}')).toStrictEqual(new MatrixError({
+            errcode: "TEST",
+        }, 500));
+    });
+
+    it("should resolve Matrix Errors from fetch", () => {
+        expect(parseErrorResponse({
+            headers: {
+                get(name: string): string | null {
+                    return name === "Content-Type" ? "application/json" : null;
+                },
+            },
+            status: 500,
+        } as Response, '{"errcode": "TEST"}')).toStrictEqual(new MatrixError({
+            errcode: "TEST",
+        }, 500));
+    });
+
+    it("should handle no type gracefully", () => {
+        expect(parseErrorResponse({
+            headers: {
+                get(name: string): string | null {
+                    return null;
+                },
+            },
+            status: 500,
+        } as Response, '{"errcode": "TEST"}')).toStrictEqual(new Error("Server returned 500 error"));
+    });
+
+    it("should handle invalid type gracefully", () => {
+        expect(parseErrorResponse({
+            headers: {
+                get(name: string): string | null {
+                    return name === "Content-Type" ? " " : null;
+                },
+            },
+            status: 500,
+        } as Response, '{"errcode": "TEST"}'))
+            .toStrictEqual(new Error("Error parsing Content-Type ' ': TypeError: invalid media type"));
+    });
+
+    it("should handle plaintext errors", () => {
+        expect(parseErrorResponse({
+            headers: {
+                get(name: string): string | null {
+                    return name === "Content-Type" ? "text/plain" : null;
+                },
+            },
+            status: 418,
+        } as Response, "I'm a teapot")).toStrictEqual(new Error("Server returned 418 error: I'm a teapot"));
+    });
+});
+
+describe("retryNetworkOperation", () => {
+    it("should retry given number of times with exponential sleeps", async () => {
+        const err = new ConnectionError("test");
+        const fn = jest.fn().mockRejectedValue(err);
+        mocked(sleep).mockResolvedValue(undefined);
+        await expect(retryNetworkOperation(4, fn)).rejects.toThrow(err);
+        expect(fn).toHaveBeenCalledTimes(4);
+        expect(mocked(sleep)).toHaveBeenCalledTimes(3);
+        expect(mocked(sleep).mock.calls[0][0]).toBe(2000);
+        expect(mocked(sleep).mock.calls[1][0]).toBe(4000);
+        expect(mocked(sleep).mock.calls[2][0]).toBe(8000);
+    });
+
+    it("should bail out on errors other than ConnectionError", async () => {
+        const err = new TypeError("invalid JSON");
+        const fn = jest.fn().mockRejectedValue(err);
+        mocked(sleep).mockResolvedValue(undefined);
+        await expect(retryNetworkOperation(3, fn)).rejects.toThrow(err);
+        expect(fn).toHaveBeenCalledTimes(1);
+    });
+
+    it("should return newest ConnectionError when giving up", async () => {
+        const err1 = new ConnectionError("test1");
+        const err2 = new ConnectionError("test2");
+        const err3 = new ConnectionError("test3");
+        const errors = [err1, err2, err3];
+        const fn = jest.fn().mockImplementation(() => {
+            throw errors.shift();
+        });
+        mocked(sleep).mockResolvedValue(undefined);
+        await expect(retryNetworkOperation(3, fn)).rejects.toThrow(err3);
+    });
+});
diff --git a/spec/unit/matrix-client.spec.ts b/spec/unit/matrix-client.spec.ts
index 2b8faf5065a..458c05f203e 100644
--- a/spec/unit/matrix-client.spec.ts
+++ b/spec/unit/matrix-client.spec.ts
@@ -103,7 +103,7 @@ describe("MatrixClient", function() {
     ];
     let acceptKeepalives: boolean;
     let pendingLookup = null;
-    function httpReq(cb, method, path, qp, data, prefix) {
+    function httpReq(method, path, qp, data, prefix) {
         if (path === KEEP_ALIVE_PATH && acceptKeepalives) {
             return Promise.resolve({
                 unstable_features: {
@@ -132,7 +132,6 @@ describe("MatrixClient", function() {
                 method: method,
                 path: path,
             };
-            pendingLookup.promise.abort = () => {}; // to make it a valid IAbortablePromise
             return pendingLookup.promise;
         }
         if (next.path === path && next.method === method) {
@@ -178,7 +177,7 @@ describe("MatrixClient", function() {
             baseUrl: "https://my.home.server",
             idBaseUrl: identityServerUrl,
             accessToken: "my.access.token",
-            request: function() {} as any, // NOP
+            fetchFn: function() {} as any, // NOP
             store: store,
             scheduler: scheduler,
             userId: userId,
@@ -1153,8 +1152,7 @@ describe("MatrixClient", function() {
 
             // event type combined
             const expectedEventType = M_BEACON_INFO.name;
-            const [callback, method, path, queryParams, requestContent] = client.http.authedRequest.mock.calls[0];
-            expect(callback).toBeFalsy();
+            const [method, path, queryParams, requestContent] = client.http.authedRequest.mock.calls[0];
             expect(method).toBe('PUT');
             expect(path).toEqual(
                 `/rooms/${encodeURIComponent(roomId)}/state/` +
@@ -1168,7 +1166,7 @@ describe("MatrixClient", function() {
             await client.unstable_setLiveBeacon(roomId, content);
 
             // event type combined
-            const [, , path, , requestContent] = client.http.authedRequest.mock.calls[0];
+            const [, path, , requestContent] = client.http.authedRequest.mock.calls[0];
             expect(path).toEqual(
                 `/rooms/${encodeURIComponent(roomId)}/state/` +
                 `${encodeURIComponent(M_BEACON_INFO.name)}/${encodeURIComponent(userId)}`,
@@ -1229,7 +1227,7 @@ describe("MatrixClient", function() {
         it("is called with plain text topic and callback and sends state event", async () => {
             const sendStateEvent = createSendStateEventMock("pizza");
             client.sendStateEvent = sendStateEvent;
-            await client.setRoomTopic(roomId, "pizza", () => {});
+            await client.setRoomTopic(roomId, "pizza");
             expect(sendStateEvent).toHaveBeenCalledTimes(1);
         });
 
@@ -1244,15 +1242,9 @@ describe("MatrixClient", function() {
     describe("setPassword", () => {
         const auth = { session: 'abcdef', type: 'foo' };
         const newPassword = 'newpassword';
-        const callback = () => {};
-
-        const passwordTest = (expectedRequestContent: any, expectedCallback?: Function) => {
-            const [callback, method, path, queryParams, requestContent] = client.http.authedRequest.mock.calls[0];
-            if (expectedCallback) {
-                expect(callback).toBe(expectedCallback);
-            } else {
-                expect(callback).toBeFalsy();
-            }
+
+        const passwordTest = (expectedRequestContent: any) => {
+            const [method, path, queryParams, requestContent] = client.http.authedRequest.mock.calls[0];
             expect(method).toBe('POST');
             expect(path).toEqual('/account/password');
             expect(queryParams).toBeFalsy();
@@ -1269,8 +1261,8 @@ describe("MatrixClient", function() {
         });
 
         it("no logout_devices specified + callback", async () => {
-            await client.setPassword(auth, newPassword, callback);
-            passwordTest({ auth, new_password: newPassword }, callback);
+            await client.setPassword(auth, newPassword);
+            passwordTest({ auth, new_password: newPassword });
         });
 
         it("overload logoutDevices=true", async () => {
@@ -1279,8 +1271,8 @@ describe("MatrixClient", function() {
         });
 
         it("overload logoutDevices=true + callback", async () => {
-            await client.setPassword(auth, newPassword, true, callback);
-            passwordTest({ auth, new_password: newPassword, logout_devices: true }, callback);
+            await client.setPassword(auth, newPassword, true);
+            passwordTest({ auth, new_password: newPassword, logout_devices: true });
         });
 
         it("overload logoutDevices=false", async () => {
@@ -1289,8 +1281,8 @@ describe("MatrixClient", function() {
         });
 
         it("overload logoutDevices=false + callback", async () => {
-            await client.setPassword(auth, newPassword, false, callback);
-            passwordTest({ auth, new_password: newPassword, logout_devices: false }, callback);
+            await client.setPassword(auth, newPassword, false);
+            passwordTest({ auth, new_password: newPassword, logout_devices: false });
         });
     });
 
@@ -1305,8 +1297,7 @@ describe("MatrixClient", function() {
             const result = await client.getLocalAliases(roomId);
 
             // Current version of the endpoint we support is v3
-            const [callback, method, path, queryParams, data, opts] = client.http.authedRequest.mock.calls[0];
-            expect(callback).toBeFalsy();
+            const [method, path, queryParams, data, opts] = client.http.authedRequest.mock.calls[0];
             expect(data).toBeFalsy();
             expect(method).toBe('GET');
             expect(path).toEqual(`/rooms/${encodeURIComponent(roomId)}/aliases`);
diff --git a/spec/unit/models/MSC3089TreeSpace.spec.ts b/spec/unit/models/MSC3089TreeSpace.spec.ts
index fdc8101ebb8..ef099fede78 100644
--- a/spec/unit/models/MSC3089TreeSpace.spec.ts
+++ b/spec/unit/models/MSC3089TreeSpace.spec.ts
@@ -890,9 +890,8 @@ describe("MSC3089TreeSpace", () => {
             expect(contents.length).toEqual(fileContents.length);
             expect(opts).toMatchObject({
                 includeFilename: false,
-                onlyContentUri: true, // because the tests rely on this - we shouldn't really be testing  for this.
             });
-            return Promise.resolve(mxc);
+            return Promise.resolve({ content_uri: mxc });
         });
         client.uploadContent = uploadFn;
 
@@ -950,9 +949,8 @@ describe("MSC3089TreeSpace", () => {
             expect(contents.length).toEqual(fileContents.length);
             expect(opts).toMatchObject({
                 includeFilename: false,
-                onlyContentUri: true, // because the tests rely on this - we shouldn't really be testing  for this.
             });
-            return Promise.resolve(mxc);
+            return Promise.resolve({ content_uri: mxc });
         });
         client.uploadContent = uploadFn;
 
diff --git a/spec/unit/pusher.spec.ts b/spec/unit/pusher.spec.ts
index 4a27ef55b5b..dd46770a4aa 100644
--- a/spec/unit/pusher.spec.ts
+++ b/spec/unit/pusher.spec.ts
@@ -16,7 +16,7 @@ limitations under the License.
 
 import MockHttpBackend from 'matrix-mock-request';
 
-import { IHttpOpts, MatrixClient, PUSHER_ENABLED } from "../../src/matrix";
+import { MatrixClient, PUSHER_ENABLED } from "../../src/matrix";
 import { mkPusher } from '../test-utils/test-utils';
 
 const realSetTimeout = setTimeout;
@@ -35,7 +35,7 @@ describe("Pushers", () => {
         client = new MatrixClient({
             baseUrl: "https://my.home.server",
             accessToken: "my.access.token",
-            request: httpBackend.requestFn as unknown as IHttpOpts["request"],
+            fetchFn: httpBackend.fetchFn as typeof global.fetch,
         });
     });
 
diff --git a/spec/unit/queueToDevice.spec.ts b/spec/unit/queueToDevice.spec.ts
index a1ae2bcfe93..c5b1f8a29d2 100644
--- a/spec/unit/queueToDevice.spec.ts
+++ b/spec/unit/queueToDevice.spec.ts
@@ -17,7 +17,7 @@ limitations under the License.
 import MockHttpBackend from 'matrix-mock-request';
 import { indexedDB as fakeIndexedDB } from 'fake-indexeddb';
 
-import { IHttpOpts, IndexedDBStore, MatrixEvent, MemoryStore, Room } from "../../src";
+import { IndexedDBStore, MatrixEvent, MemoryStore, Room } from "../../src";
 import { MatrixClient } from "../../src/client";
 import { ToDeviceBatch } from '../../src/models/ToDeviceMessage';
 import { logger } from '../../src/logger';
@@ -89,7 +89,7 @@ describe.each([
         client = new MatrixClient({
             baseUrl: "https://my.home.server",
             accessToken: "my.access.token",
-            request: httpBackend.requestFn as IHttpOpts["request"],
+            fetchFn: httpBackend.fetchFn as typeof global.fetch,
             store,
         });
     });
diff --git a/spec/unit/read-receipt.spec.ts b/spec/unit/read-receipt.spec.ts
index 2e906a3cc41..07acaa184dd 100644
--- a/spec/unit/read-receipt.spec.ts
+++ b/spec/unit/read-receipt.spec.ts
@@ -18,7 +18,6 @@ import MockHttpBackend from 'matrix-mock-request';
 
 import { ReceiptType } from '../../src/@types/read_receipts';
 import { MatrixClient } from "../../src/client";
-import { IHttpOpts } from '../../src/http-api';
 import { EventType } from '../../src/matrix';
 import { MAIN_ROOM_TIMELINE } from '../../src/models/read-receipt';
 import { encodeUri } from '../../src/utils';
@@ -87,7 +86,7 @@ describe("Read receipt", () => {
         client = new MatrixClient({
             baseUrl: "https://my.home.server",
             accessToken: "my.access.token",
-            request: httpBackend.requestFn as unknown as IHttpOpts["request"],
+            fetchFn: httpBackend.fetchFn as typeof global.fetch,
         });
         client.isGuest = () => false;
     });
@@ -146,5 +145,23 @@ describe("Read receipt", () => {
             await httpBackend.flushAllExpected();
             await flushPromises();
         });
+
+        it("sends a valid room read receipt even when body omitted", async () => {
+            httpBackend.when(
+                "POST", encodeUri("/rooms/$roomId/receipt/$receiptType/$eventId", {
+                    $roomId: ROOM_ID,
+                    $receiptType: ReceiptType.Read,
+                    $eventId: threadEvent.getId(),
+                }),
+            ).check((request) => {
+                expect(request.data).toEqual({});
+            }).respond(200, {});
+
+            mockServerSideSupport(client, false);
+            client.sendReceipt(threadEvent, ReceiptType.Read, undefined);
+
+            await httpBackend.flushAllExpected();
+            await flushPromises();
+        });
     });
 });
diff --git a/spec/unit/utils.spec.ts b/spec/unit/utils.spec.ts
index 5d804022ede..1b11f2a7cd3 100644
--- a/spec/unit/utils.spec.ts
+++ b/spec/unit/utils.spec.ts
@@ -26,9 +26,7 @@ describe("utils", function() {
                 foo: "bar",
                 baz: "beer@",
             };
-            expect(utils.encodeParams(params)).toEqual(
-                "foo=bar&baz=beer%40",
-            );
+            expect(utils.encodeParams(params).toString()).toEqual("foo=bar&baz=beer%40");
         });
 
         it("should handle boolean and numeric values", function() {
@@ -37,7 +35,24 @@ describe("utils", function() {
                 number: 12345,
                 boolean: false,
             };
-            expect(utils.encodeParams(params)).toEqual("string=foobar&number=12345&boolean=false");
+            expect(utils.encodeParams(params).toString()).toEqual("string=foobar&number=12345&boolean=false");
+        });
+
+        it("should handle string arrays", () => {
+            const params = {
+                via: ["one", "two", "three"],
+            };
+            expect(utils.encodeParams(params).toString()).toEqual("via=one&via=two&via=three");
+        });
+    });
+
+    describe("decodeParams", () => {
+        it("should be able to decode multiple values into an array", () => {
+            const params = "foo=bar&via=a&via=b&via=c";
+            expect(utils.decodeParams(params)).toEqual({
+                foo: "bar",
+                via: ["a", "b", "c"],
+            });
         });
     });
 
diff --git a/src/@types/global.d.ts b/src/@types/global.d.ts
index 679a6afba6e..6b512434902 100644
--- a/src/@types/global.d.ts
+++ b/src/@types/global.d.ts
@@ -30,6 +30,8 @@ declare global {
     namespace NodeJS {
         interface Global {
             localStorage: Storage;
+            // marker variable used to detect both the browser & node entrypoints being used at once
+            __js_sdk_entrypoint: unknown;
         }
     }
 
diff --git a/src/@types/partials.ts b/src/@types/partials.ts
index a729d80dc64..bf27eab0e53 100644
--- a/src/@types/partials.ts
+++ b/src/@types/partials.ts
@@ -40,11 +40,6 @@ export enum Preset {
 
 export type ResizeMethod = "crop" | "scale";
 
-// TODO move to http-api after TSification
-export interface IAbortablePromise<T> extends Promise<T> {
-    abort(): void;
-}
-
 export type IdServerUnbindResult = "no-support" | "success";
 
 // Knock and private are reserved keywords which are not yet implemented.
diff --git a/src/@types/requests.ts b/src/@types/requests.ts
index cb292bf2cf0..f9095455e15 100644
--- a/src/@types/requests.ts
+++ b/src/@types/requests.ts
@@ -14,7 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { Callback } from "../client";
 import { IContent, IEvent } from "../models/event";
 import { Preset, Visibility } from "./partials";
 import { IEventWithRoomId, SearchKey } from "./search";
@@ -130,16 +129,6 @@ export interface IRoomDirectoryOptions {
     third_party_instance_id?: string;
 }
 
-export interface IUploadOpts {
-    name?: string;
-    includeFilename?: boolean;
-    type?: string;
-    rawResponse?: boolean;
-    onlyContentUri?: boolean;
-    callback?: Callback;
-    progressHandler?: (state: {loaded: number, total: number}) => void;
-}
-
 export interface IAddThreePidOnlyBody {
     auth?: {
         type: string;
diff --git a/src/ToDeviceMessageQueue.ts b/src/ToDeviceMessageQueue.ts
index 12827d8bbc8..aaff912de69 100644
--- a/src/ToDeviceMessageQueue.ts
+++ b/src/ToDeviceMessageQueue.ts
@@ -28,7 +28,7 @@ const MAX_BATCH_SIZE = 20;
 export class ToDeviceMessageQueue {
     private sending = false;
     private running = true;
-    private retryTimeout: number = null;
+    private retryTimeout: ReturnType<typeof setTimeout> | null = null;
     private retryAttempts = 0;
 
     constructor(private client: MatrixClient) {
@@ -68,7 +68,7 @@ export class ToDeviceMessageQueue {
         logger.debug("Attempting to send queued to-device messages");
 
         this.sending = true;
-        let headBatch;
+        let headBatch: IndexedToDeviceBatch;
         try {
             while (this.running) {
                 headBatch = await this.client.store.getOldestToDeviceBatch();
@@ -92,7 +92,7 @@ export class ToDeviceMessageQueue {
                 // bored and giving up for now
                 if (Math.floor(e.httpStatus / 100) === 4) {
                     logger.error("Fatal error when sending to-device message - dropping to-device batch!", e);
-                    await this.client.store.removeToDeviceBatch(headBatch.id);
+                    await this.client.store.removeToDeviceBatch(headBatch!.id);
                 } else {
                     logger.info("Automatic retry limit reached for to-device messages.");
                 }
diff --git a/src/autodiscovery.ts b/src/autodiscovery.ts
index 71cbd2105f9..8bf87e5177e 100644
--- a/src/autodiscovery.ts
+++ b/src/autodiscovery.ts
@@ -17,10 +17,9 @@ limitations under the License.
 
 /** @module auto-discovery */
 
-import { ServerResponse } from "http";
-
 import { IClientWellKnown, IWellKnownConfig } from "./client";
 import { logger } from './logger';
+import { MatrixError, Method, timeoutSignal } from "./http-api";
 
 // Dev note: Auto discovery is part of the spec.
 // See: https://matrix.org/docs/spec/client_server/r0.4.0.html#server-discovery
@@ -395,6 +394,19 @@ export class AutoDiscovery {
         }
     }
 
+    private static fetch(resource: URL | string, options?: RequestInit): ReturnType<typeof global.fetch> {
+        if (this.fetchFn) {
+            return this.fetchFn(resource, options);
+        }
+        return global.fetch(resource, options);
+    }
+
+    private static fetchFn?: typeof global.fetch;
+
+    public static setFetchFn(fetchFn: typeof global.fetch): void {
+        AutoDiscovery.fetchFn = fetchFn;
+    }
+
     /**
      * Fetches a JSON object from a given URL, as expected by all .well-known
      * related lookups. If the server gives a 404 then the `action` will be
@@ -411,45 +423,55 @@ export class AutoDiscovery {
      * @return {Promise<object>} Resolves to the returned state.
      * @private
      */
-    private static fetchWellKnownObject(uri: string): Promise<IWellKnownConfig> {
-        return new Promise((resolve) => {
-            // eslint-disable-next-line
-            const request = require("./matrix").getRequest();
-            if (!request) throw new Error("No request library available");
-            request(
-                { method: "GET", uri, timeout: 5000 },
-                (error: Error, response: ServerResponse, body: string) => {
-                    if (error || response?.statusCode < 200 || response?.statusCode >= 300) {
-                        const result = { error, raw: {} };
-                        return resolve(response?.statusCode === 404
-                            ? {
-                                ...result,
-                                action: AutoDiscoveryAction.IGNORE,
-                                reason: AutoDiscovery.ERROR_MISSING_WELLKNOWN,
-                            } : {
-                                ...result,
-                                action: AutoDiscoveryAction.FAIL_PROMPT,
-                                reason: error?.message || "General failure",
-                            });
-                    }
-
-                    try {
-                        return resolve({
-                            raw: JSON.parse(body),
-                            action: AutoDiscoveryAction.SUCCESS,
-                        });
-                    } catch (err) {
-                        return resolve({
-                            error: err,
-                            raw: {},
-                            action: AutoDiscoveryAction.FAIL_PROMPT,
-                            reason: err?.name === "SyntaxError"
-                                ? AutoDiscovery.ERROR_INVALID_JSON
-                                : AutoDiscovery.ERROR_INVALID,
-                        });
-                    }
-                },
-            );
-        });
+    private static async fetchWellKnownObject(url: string): Promise<IWellKnownConfig> {
+        let response: Response;
+
+        try {
+            response = await AutoDiscovery.fetch(url, {
+                method: Method.Get,
+                signal: timeoutSignal(5000),
+            });
+
+            if (response.status === 404) {
+                return {
+                    raw: {},
+                    action: AutoDiscoveryAction.IGNORE,
+                    reason: AutoDiscovery.ERROR_MISSING_WELLKNOWN,
+                };
+            }
+
+            if (!response.ok) {
+                return {
+                    raw: {},
+                    action: AutoDiscoveryAction.FAIL_PROMPT,
+                    reason: "General failure",
+                };
+            }
+        } catch (err) {
+            const error = err as Error | string | undefined;
+            return {
+                error,
+                raw: {},
+                action: AutoDiscoveryAction.FAIL_PROMPT,
+                reason: (<Error>error)?.message || "General failure",
+            };
+        }
+
+        try {
+            return {
+                raw: await response.json(),
+                action: AutoDiscoveryAction.SUCCESS,
+            };
+        } catch (err) {
+            const error = err as Error | string | undefined;
+            return {
+                error,
+                raw: {},
+                action: AutoDiscoveryAction.FAIL_PROMPT,
+                reason: (error as MatrixError)?.name === "SyntaxError"
+                    ? AutoDiscovery.ERROR_INVALID_JSON
+                    : AutoDiscovery.ERROR_INVALID,
+            };
+        }
     }
 }
diff --git a/src/browser-index.js b/src/browser-index.js
index 3e3627fa9d8..86e887bd49f 100644
--- a/src/browser-index.js
+++ b/src/browser-index.js
@@ -14,25 +14,12 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import request from "browser-request";
-import queryString from "qs";
-
 import * as matrixcs from "./matrix";
 
-if (matrixcs.getRequest()) {
+if (global.__js_sdk_entrypoint) {
     throw new Error("Multiple matrix-js-sdk entrypoints detected!");
 }
-
-matrixcs.request(function(opts, fn) {
-    // We manually fix the query string for browser-request because
-    // it doesn't correctly handle cases like ?via=one&via=two. Instead
-    // we mimic `request`'s query string interface to make it all work
-    // as expected.
-    // browser-request will happily take the constructed string as the
-    // query string without trying to modify it further.
-    opts.qs = queryString.stringify(opts.qs || {}, opts.qsStringifyOptions);
-    return request(opts, fn);
-});
+global.__js_sdk_entrypoint = true;
 
 // just *accessing* indexedDB throws an exception in firefox with
 // indexeddb disabled.
diff --git a/src/client.ts b/src/client.ts
index a8857abbbe1..d8392ae924c 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -36,7 +36,7 @@ import { CallEvent, CallEventHandlerMap, createNewMatrixCall, MatrixCall, suppor
 import { Filter, IFilterDefinition, IRoomEventFilter } from "./filter";
 import { CallEventHandlerEvent, CallEventHandler, CallEventHandlerEventHandlerMap } from './webrtc/callEventHandler';
 import * as utils from './utils';
-import { sleep } from './utils';
+import { QueryDict, sleep } from './utils';
 import { Direction, EventTimeline } from "./models/event-timeline";
 import { IActionsObject, PushProcessor } from "./pushprocessor";
 import { AutoDiscovery, AutoDiscoveryAction } from "./autodiscovery";
@@ -49,22 +49,17 @@ import { IRoomEncryption, RoomList } from './crypto/RoomList';
 import { logger } from './logger';
 import { SERVICE_TYPES } from './service-types';
 import {
-    FileType,
     HttpApiEvent,
     HttpApiEventHandlerMap,
-    IHttpOpts,
-    IUpload,
+    Upload,
+    UploadOpts,
     MatrixError,
     MatrixHttpApi,
     Method,
-    PREFIX_IDENTITY_V2,
-    PREFIX_MEDIA_R0,
-    PREFIX_R0,
-    PREFIX_UNSTABLE,
-    PREFIX_V1,
-    PREFIX_V3,
     retryNetworkOperation,
-    UploadContentResponseType,
+    ClientPrefix,
+    MediaPrefix,
+    IdentityPrefix, IHttpOpts, FileType, UploadResponse,
 } from "./http-api";
 import {
     Crypto,
@@ -154,7 +149,6 @@ import {
     IRoomDirectoryOptions,
     ISearchOpts,
     ISendEventResponse,
-    IUploadOpts,
 } from "./@types/requests";
 import {
     EventType,
@@ -168,7 +162,7 @@ import {
     UNSTABLE_MSC3088_PURPOSE,
     UNSTABLE_MSC3089_TREE_SUBTYPE,
 } from "./@types/event";
-import { IAbortablePromise, IdServerUnbindResult, IImageInfo, Preset, Visibility } from "./@types/partials";
+import { IdServerUnbindResult, IImageInfo, Preset, Visibility } from "./@types/partials";
 import { EventMapper, eventMapperFor, MapperOpts } from "./event-mapper";
 import { randomString } from "./randomstring";
 import { BackupManager, IKeyBackup, IKeyBackupCheck, IPreparedKeyBackupVersion, TrustInfo } from "./crypto/backup";
@@ -209,7 +203,6 @@ import { buildFeatureSupportMap, Feature, ServerSupport } from "./feature";
 
 export type Store = IStore;
 
-export type Callback<T = any> = (err: Error | any | null, data?: T) => void;
 export type ResetTimelineCallback = (roomId: string) => boolean;
 
 const SCROLLBACK_DELAY_MS = 3000;
@@ -262,12 +255,10 @@ export interface ICreateClientOpts {
     scheduler?: MatrixScheduler;
 
     /**
-     * The function to invoke for HTTP
-     * requests. The value of this property is typically <code>require("request")
-     * </code> as it returns a function which meets the required interface. See
-     * {@link requestFunction} for more information.
+     * The function to invoke for HTTP requests.
+     * Most supported environments have a global `fetch` registered to which this will fall back.
      */
-    request?: IHttpOpts["request"];
+    fetchFn?: typeof global.fetch;
 
     userId?: string;
 
@@ -622,7 +613,7 @@ export interface IUploadKeysRequest {
     "org.matrix.msc2732.fallback_keys"?: Record<string, IOneTimeKey>;
 }
 
-interface IOpenIDToken {
+export interface IOpenIDToken {
     access_token: string;
     token_type: "Bearer" | string;
     matrix_server_name: string;
@@ -930,15 +921,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     public olmVersion: [number, number, number] = null; // populated after initCrypto
     public usingExternalCrypto = false;
     public store: Store;
-    public deviceId?: string;
+    public deviceId: string | null;
     public credentials: { userId?: string };
-    public pickleKey: string;
+    public pickleKey?: string;
     public scheduler: MatrixScheduler;
     public clientRunning = false;
     public timelineSupport = false;
     public urlPreviewCache: { [key: string]: Promise<IPreviewUrlResponse> } = {};
     public identityServer: IIdentityServerProvider;
-    public http: MatrixHttpApi; // XXX: Intended private, used in code.
+    public http: MatrixHttpApi<IHttpOpts & { onlyData: true }>; // XXX: Intended private, used in code.
     public crypto?: Crypto; // XXX: Intended private, used in code.
     public cryptoCallbacks: ICryptoCallbacks; // XXX: Intended private, used in code.
     public callEventHandler: CallEventHandler; // XXX: Intended private, used in code.
@@ -1007,7 +998,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         this.idBaseUrl = opts.idBaseUrl;
         this.identityServer = opts.identityServer;
 
-        this.usingExternalCrypto = opts.usingExternalCrypto;
+        this.usingExternalCrypto = opts.usingExternalCrypto ?? false;
         this.store = opts.store || new StubStore();
         this.deviceId = opts.deviceId || null;
 
@@ -1015,11 +1006,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         this.credentials = { userId };
 
         this.http = new MatrixHttpApi(this as ConstructorParameters<typeof MatrixHttpApi>[0], {
+            fetchFn: opts.fetchFn,
             baseUrl: opts.baseUrl,
             idBaseUrl: opts.idBaseUrl,
             accessToken: opts.accessToken,
-            request: opts.request,
-            prefix: PREFIX_R0,
+            prefix: ClientPrefix.R0,
             onlyData: true,
             extraParams: opts.queryParams,
             localTimeoutMs: opts.localTimeoutMs,
@@ -1315,7 +1306,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             logger.log("unpickled device");
 
             const rehydrateResult = await this.http.authedRequest<{ success: boolean }>(
-                undefined,
                 Method.Post,
                 "/dehydrated_device/claim",
                 undefined,
@@ -1356,7 +1346,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     public async getDehydratedDevice(): Promise<IDehydratedDevice> {
         try {
             return await this.http.authedRequest<IDehydratedDevice>(
-                undefined,
                 Method.Get,
                 "/dehydrated_device",
                 undefined, undefined,
@@ -1649,9 +1638,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
         }
 
-        return this.http.authedRequest(
-            undefined, Method.Get, "/capabilities",
-        ).catch((e: Error): void => {
+        return this.http.authedRequest(Method.Get, "/capabilities").catch((e: Error): void => {
             // We swallow errors because we need a default object anyhow
             logger.error(e);
         }).then((r: { capabilities?: ICapabilities } = {}) => {
@@ -2271,7 +2258,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
     /**
      * Counts the number of end to end session keys that are waiting to be backed up
-     * @returns {Promise<int>} Resolves to the number of sessions requiring backup
+     * @returns {Promise<number>} Resolves to the number of sessions requiring backup
      */
     public countSessionsNeedingBackup(): Promise<number> {
         if (!this.crypto) {
@@ -2683,8 +2670,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         let res: IKeyBackupInfo;
         try {
             res = await this.http.authedRequest<IKeyBackupInfo>(
-                undefined, Method.Get, "/room_keys/version", undefined, undefined,
-                { prefix: PREFIX_V3 },
+                Method.Get, "/room_keys/version", undefined, undefined,
+                { prefix: ClientPrefix.V3 },
             );
         } catch (e) {
             if (e.errcode === 'M_NOT_FOUND') {
@@ -2839,8 +2826,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         const res = await this.http.authedRequest<IKeyBackupInfo>(
-            undefined, Method.Post, "/room_keys/version", undefined, data,
-            { prefix: PREFIX_V3 },
+            Method.Post, "/room_keys/version", undefined, data,
+            { prefix: ClientPrefix.V3 },
         );
 
         // We could assume everything's okay and enable directly, but this ensures
@@ -2854,7 +2841,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         return res;
     }
 
-    public deleteKeyBackupVersion(version: string): Promise<void> {
+    public async deleteKeyBackupVersion(version: string): Promise<void> {
         if (!this.crypto) {
             throw new Error("End-to-end encryption disabled");
         }
@@ -2870,20 +2857,16 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $version: version,
         });
 
-        return this.http.authedRequest(
-            undefined, Method.Delete, path, undefined, undefined,
-            { prefix: PREFIX_V3 },
+        await this.http.authedRequest(
+            Method.Delete, path, undefined, undefined,
+            { prefix: ClientPrefix.V3 },
         );
     }
 
-    private makeKeyBackupPath(roomId: undefined, sessionId: undefined, version: string): IKeyBackupPath;
-    private makeKeyBackupPath(roomId: string, sessionId: undefined, version: string): IKeyBackupPath;
-    private makeKeyBackupPath(roomId: string, sessionId: string, version: string): IKeyBackupPath;
-    private makeKeyBackupPath(
-        roomId: string | undefined,
-        sessionId: string | undefined,
-        version: string,
-    ): IKeyBackupPath {
+    private makeKeyBackupPath(roomId: undefined, sessionId: undefined, version?: string): IKeyBackupPath;
+    private makeKeyBackupPath(roomId: string, sessionId: undefined, version?: string): IKeyBackupPath;
+    private makeKeyBackupPath(roomId: string, sessionId: string, version?: string): IKeyBackupPath;
+    private makeKeyBackupPath(roomId?: string, sessionId?: string, version?: string): IKeyBackupPath {
         let path;
         if (sessionId !== undefined) {
             path = utils.encodeUri("/room_keys/keys/$roomId/$sessionId", {
@@ -2910,11 +2893,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @return {Promise} a promise that will resolve when the keys
      * are uploaded
      */
-    public sendKeyBackup(roomId: undefined, sessionId: undefined, version: string, data: IKeyBackup): Promise<void>;
-    public sendKeyBackup(roomId: string, sessionId: undefined, version: string, data: IKeyBackup): Promise<void>;
-    public sendKeyBackup(roomId: string, sessionId: string, version: string, data: IKeyBackup): Promise<void>;
+    public sendKeyBackup(
+        roomId: undefined,
+        sessionId: undefined,
+        version: string | undefined,
+        data: IKeyBackup,
+    ): Promise<void>;
     public sendKeyBackup(
         roomId: string,
+        sessionId: undefined,
+        version: string | undefined,
+        data: IKeyBackup,
+    ): Promise<void>;
+    public sendKeyBackup(
+        roomId: string,
+        sessionId: string,
+        version: string | undefined,
+        data: IKeyBackup,
+    ): Promise<void>;
+    public async sendKeyBackup(
+        roomId: string | undefined,
         sessionId: string | undefined,
         version: string | undefined,
         data: IKeyBackup,
@@ -2924,9 +2922,9 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         const path = this.makeKeyBackupPath(roomId, sessionId, version);
-        return this.http.authedRequest(
-            undefined, Method.Put, path.path, path.queryData, data,
-            { prefix: PREFIX_UNSTABLE },
+        await this.http.authedRequest(
+            Method.Put, path.path, path.queryData, data,
+            { prefix: ClientPrefix.Unstable },
         );
     }
 
@@ -2945,7 +2943,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * Marks all group sessions as needing to be backed up without scheduling
      * them to upload in the background.
-     * @returns {Promise<int>} Resolves to the number of sessions requiring a backup.
+     * @returns {Promise<number>} Resolves to the number of sessions requiring a backup.
      */
     public flagAllGroupSessionsForBackup(): Promise<number> {
         if (!this.crypto) {
@@ -3216,8 +3214,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
 
             const res = await this.http.authedRequest<IRoomsKeysResponse | IRoomKeysResponse | IKeyBackupSession>(
-                undefined, Method.Get, path.path, path.queryData, undefined,
-                { prefix: PREFIX_UNSTABLE },
+                Method.Get, path.path, path.queryData, undefined,
+                { prefix: ClientPrefix.Unstable },
             );
 
             if ((res as IRoomsKeysResponse).rooms) {
@@ -3267,22 +3265,18 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         return { total: totalKeyCount, imported: keys.length };
     }
 
-    public deleteKeysFromBackup(roomId: undefined, sessionId: undefined, version: string): Promise<void>;
-    public deleteKeysFromBackup(roomId: string, sessionId: undefined, version: string): Promise<void>;
-    public deleteKeysFromBackup(roomId: string, sessionId: string, version: string): Promise<void>;
-    public deleteKeysFromBackup(
-        roomId: string | undefined,
-        sessionId: string | undefined,
-        version: string,
-    ): Promise<void> {
+    public deleteKeysFromBackup(roomId: undefined, sessionId: undefined, version?: string): Promise<void>;
+    public deleteKeysFromBackup(roomId: string, sessionId: undefined, version?: string): Promise<void>;
+    public deleteKeysFromBackup(roomId: string, sessionId: string, version?: string): Promise<void>;
+    public async deleteKeysFromBackup(roomId?: string, sessionId?: string, version?: string): Promise<void> {
         if (!this.crypto) {
             throw new Error("End-to-end encryption disabled");
         }
 
         const path = this.makeKeyBackupPath(roomId, sessionId, version);
-        return this.http.authedRequest(
-            undefined, Method.Delete, path.path, path.queryData, undefined,
-            { prefix: PREFIX_UNSTABLE },
+        await this.http.authedRequest(
+            Method.Delete, path.path, path.queryData, undefined,
+            { prefix: ClientPrefix.Unstable },
         );
     }
 
@@ -3322,13 +3316,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
     /**
      * Get the config for the media repository.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves with an object containing the config.
      */
-    public getMediaConfig(callback?: Callback): Promise<IMediaConfig> {
+    public getMediaConfig(): Promise<IMediaConfig> {
         return this.http.authedRequest(
-            callback, Method.Get, "/config", undefined, undefined, {
-                prefix: PREFIX_MEDIA_R0,
+            Method.Get, "/config", undefined, undefined, {
+                prefix: MediaPrefix.R0,
             },
         );
     }
@@ -3410,22 +3403,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * It will retry the request up to 5 times.
      * @param {string} eventType The event type
      * @param {Object} content the contents object for the event
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: an empty object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setAccountData(eventType: EventType | string, content: IContent, callback?: Callback): Promise<{}> {
+    public setAccountData(eventType: EventType | string, content: IContent): Promise<{}> {
         const path = utils.encodeUri("/user/$userId/account_data/$type", {
             $userId: this.credentials.userId,
             $type: eventType,
         });
-        const promise = retryNetworkOperation(5, () => {
-            return this.http.authedRequest(undefined, Method.Put, path, undefined, content);
+        return retryNetworkOperation(5, () => {
+            return this.http.authedRequest(Method.Put, path, undefined, content);
         });
-        if (callback) {
-            promise.then(result => callback(null, result), callback);
-        }
-        return promise;
     }
 
     /**
@@ -3442,11 +3430,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * gets account data directly from the homeserver if the local store is not
      * ready, which can be useful very early in startup before the initial sync.
      * @param {string} eventType The event type
-     * @return {Promise} Resolves: The contents of the given account
-     * data event.
+     * @return {Promise} Resolves: The contents of the given account data event.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async getAccountDataFromServer<T extends {[k: string]: any}>(eventType: string): Promise<T> {
+    public async getAccountDataFromServer<T extends {[k: string]: any}>(eventType: string): Promise<T | null> {
         if (this.isInitialSyncComplete()) {
             const event = this.store.getAccountData(eventType);
             if (!event) {
@@ -3454,14 +3441,14 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
             // The network version below returns just the content, so this branch
             // does the same to match.
-            return event.getContent();
+            return event.getContent<T>();
         }
         const path = utils.encodeUri("/user/$userId/account_data/$type", {
             $userId: this.credentials.userId,
             $type: eventType,
         });
         try {
-            return await this.http.authedRequest(undefined, Method.Get, path);
+            return await this.http.authedRequest(Method.Get, path);
         } catch (e) {
             if (e.data?.errcode === 'M_NOT_FOUND') {
                 return null;
@@ -3483,16 +3470,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * Sets the users that the current user should ignore.
      * @param {string[]} userIds the user IDs to ignore
-     * @param {module:client.callback} [callback] Optional.
      * @return {Promise} Resolves: an empty object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setIgnoredUsers(userIds: string[], callback?: Callback): Promise<{}> {
+    public setIgnoredUsers(userIds: string[]): Promise<{}> {
         const content = { ignored_users: {} };
         userIds.forEach((u) => {
             content.ignored_users[u] = {};
         });
-        return this.setAccountData("m.ignored_user_list", content, callback);
+        return this.setAccountData("m.ignored_user_list", content);
     }
 
     /**
@@ -3513,31 +3499,25 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * </strong> Default: true.
      * @param {boolean} opts.inviteSignUrl If the caller has a keypair 3pid invite, the signing URL is passed in this parameter.
      * @param {string[]} opts.viaServers The server names to try and join through in addition to those that are automatically chosen.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Room object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async joinRoom(roomIdOrAlias: string, opts?: IJoinRoomOpts, callback?: Callback): Promise<Room> {
-        // to help people when upgrading..
-        if (utils.isFunction(opts)) {
-            throw new Error("Expected 'opts' object, got function.");
-        }
-        opts = opts || {};
+    public async joinRoom(roomIdOrAlias: string, opts: IJoinRoomOpts = {}): Promise<Room> {
         if (opts.syncRoom === undefined) {
             opts.syncRoom = true;
         }
 
         const room = this.getRoom(roomIdOrAlias);
-        if (room && room.hasMembershipState(this.credentials.userId, "join")) {
+        if (room?.hasMembershipState(this.credentials.userId, "join")) {
             return Promise.resolve(room);
         }
 
         let signPromise: Promise<IThirdPartySigned | void> = Promise.resolve();
 
         if (opts.inviteSignUrl) {
-            signPromise = this.http.requestOtherUrl(
-                undefined, Method.Post,
-                opts.inviteSignUrl, { mxid: this.credentials.userId },
+            signPromise = this.http.requestOtherUrl<IThirdPartySigned>(
+                Method.Post,
+                new URL(opts.inviteSignUrl), { mxid: this.credentials.userId },
             );
         }
 
@@ -3546,8 +3526,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             queryString["server_name"] = opts.viaServers;
         }
 
-        const reqOpts = { qsStringifyOptions: { arrayFormat: 'repeat' } };
-
         try {
             const data: IJoinRequestBody = {};
             const signedInviteObj = await signPromise;
@@ -3556,7 +3534,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
 
             const path = utils.encodeUri("/join/$roomid", { $roomid: roomIdOrAlias });
-            const res = await this.http.authedRequest(undefined, Method.Post, path, queryString, data, reqOpts);
+            const res = await this.http.authedRequest(Method.Post, path, queryString, data);
 
             const roomId = res['room_id'];
             const syncApi = new SyncApi(this, this.clientOpts);
@@ -3565,10 +3543,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 // v2 will do this for us
                 // return syncApi.syncRoom(room);
             }
-            callback?.(null, room);
             return room;
         } catch (e) {
-            callback?.(e);
             throw e; // rethrow for reject
         }
     }
@@ -3617,19 +3593,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * @param {string} roomId
      * @param {string} name
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setRoomName(roomId: string, name: string, callback?: Callback): Promise<ISendEventResponse> {
-        return this.sendStateEvent(roomId, EventType.RoomName, { name: name }, undefined, callback);
+    public setRoomName(roomId: string, name: string): Promise<ISendEventResponse> {
+        return this.sendStateEvent(roomId, EventType.RoomName, { name: name });
     }
 
     /**
      * @param {string} roomId
      * @param {string} topic
      * @param {string} htmlTopic Optional.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -3637,76 +3611,59 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         topic: string,
         htmlTopic?: string,
-    ): Promise<ISendEventResponse>;
-    public setRoomTopic(
-        roomId: string,
-        topic: string,
-        callback?: Callback,
-    ): Promise<ISendEventResponse>;
-    public setRoomTopic(
-        roomId: string,
-        topic: string,
-        htmlTopicOrCallback?: string | Callback,
     ): Promise<ISendEventResponse> {
-        const isCallback = typeof htmlTopicOrCallback === 'function';
-        const htmlTopic = isCallback ? undefined : htmlTopicOrCallback;
-        const callback = isCallback ? htmlTopicOrCallback : undefined;
         const content = ContentHelpers.makeTopicContent(topic, htmlTopic);
-        return this.sendStateEvent(roomId, EventType.RoomTopic, content, undefined, callback);
+        return this.sendStateEvent(roomId, EventType.RoomTopic, content);
     }
 
     /**
      * @param {string} roomId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an object keyed by tagId with objects containing a numeric order field.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public getRoomTags(roomId: string, callback?: Callback): Promise<ITagsResponse> {
+    public getRoomTags(roomId: string): Promise<ITagsResponse> {
         const path = utils.encodeUri("/user/$userId/rooms/$roomId/tags", {
             $userId: this.credentials.userId,
             $roomId: roomId,
         });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
      * @param {string} roomId
      * @param {string} tagName name of room tag to be set
      * @param {object} metadata associated with that tag to be stored
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setRoomTag(roomId: string, tagName: string, metadata: ITagMetadata, callback?: Callback): Promise<{}> {
+    public setRoomTag(roomId: string, tagName: string, metadata: ITagMetadata): Promise<{}> {
         const path = utils.encodeUri("/user/$userId/rooms/$roomId/tags/$tag", {
             $userId: this.credentials.userId,
             $roomId: roomId,
             $tag: tagName,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, metadata);
+        return this.http.authedRequest(Method.Put, path, undefined, metadata);
     }
 
     /**
      * @param {string} roomId
      * @param {string} tagName name of room tag to be removed
-     * @param {module:client.callback} callback Optional.
-     * @return {Promise} Resolves: void
+     * @return {Promise} Resolves: to an empty object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public deleteRoomTag(roomId: string, tagName: string, callback?: Callback): Promise<void> {
+    public deleteRoomTag(roomId: string, tagName: string): Promise<{}> {
         const path = utils.encodeUri("/user/$userId/rooms/$roomId/tags/$tag", {
             $userId: this.credentials.userId,
             $roomId: roomId,
             $tag: tagName,
         });
-        return this.http.authedRequest(callback, Method.Delete, path);
+        return this.http.authedRequest(Method.Delete, path);
     }
 
     /**
      * @param {string} roomId
      * @param {string} eventType event type to be set
      * @param {object} content event content
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -3714,14 +3671,13 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         eventType: string,
         content: Record<string, any>,
-        callback?: Callback,
     ): Promise<{}> {
         const path = utils.encodeUri("/user/$userId/rooms/$roomId/account_data/$type", {
             $userId: this.credentials.userId,
             $roomId: roomId,
             $type: eventType,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, content);
+        return this.http.authedRequest(Method.Put, path, undefined, content);
     }
 
     /**
@@ -3730,7 +3686,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} userId
      * @param {Number} powerLevel
      * @param {MatrixEvent} event
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -3739,7 +3694,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         userId: string,
         powerLevel: number,
         event: MatrixEvent,
-        callback?: Callback,
     ): Promise<ISendEventResponse> {
         let content = {
             users: {},
@@ -3753,7 +3707,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const path = utils.encodeUri("/rooms/$roomId/state/m.room.power_levels", {
             $roomId: roomId,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, content);
+        return this.http.authedRequest(Method.Put, path, undefined, content);
     }
 
     /**
@@ -3792,7 +3746,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} eventType
      * @param {Object} content
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -3801,7 +3754,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         eventType: string,
         content: IContent,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendEvent(
         roomId: string,
@@ -3809,18 +3761,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         eventType: string,
         content: IContent,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendEvent(
         roomId: string,
         threadId: string | null,
         eventType: string | IContent,
         content: IContent | string,
-        txnId?: string | Callback,
-        callback?: Callback,
+        txnId?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = txnId as Callback;
             txnId = content as string;
             content = eventType as IContent;
             eventType = threadId;
@@ -3848,7 +3797,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
         }
 
-        return this.sendCompleteEvent(roomId, threadId, { type: eventType, content }, txnId as string, callback);
+        return this.sendCompleteEvent(roomId, threadId, { type: eventType, content }, txnId);
     }
 
     /**
@@ -3856,7 +3805,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {object} eventObject An object with the partial structure of an event, to which event_id, user_id, room_id and origin_server_ts will be added.
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -3865,13 +3813,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         threadId: string | null,
         eventObject: any,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse> {
-        if (utils.isFunction(txnId)) {
-            callback = txnId as any as Callback; // convert for legacy
-            txnId = undefined;
-        }
-
         if (!txnId) {
             txnId = this.makeTxnId();
         }
@@ -3929,18 +3871,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             return Promise.reject(new Error("Event blocked by other events not yet sent"));
         }
 
-        return this.encryptAndSendEvent(room, localEvent, callback);
+        return this.encryptAndSendEvent(room, localEvent);
     }
 
     /**
      * encrypts the event if necessary; adds the event to the queue, or sends it; marks the event as sent/unsent
      * @param room
      * @param event
-     * @param callback
      * @returns {Promise} returns a promise which resolves with the result of the send request
      * @private
      */
-    private encryptAndSendEvent(room: Room, event: MatrixEvent, callback?: Callback): Promise<ISendEventResponse> {
+    private encryptAndSendEvent(room: Room, event: MatrixEvent): Promise<ISendEventResponse> {
         let cancelled = false;
         // Add an extra Promise.resolve() to turn synchronous exceptions into promise rejections,
         // so that we can handle synchronous and asynchronous exceptions with the
@@ -3986,9 +3927,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
 
             return promise;
-        }).then(res => {
-            callback?.(null, res);
-            return res;
         }).catch(err => {
             logger.error("Error sending event", err.stack || err);
             try {
@@ -4000,8 +3938,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 // also put the event object on the error: the caller will need this
                 // to resend or cancel the event
                 err.event = event;
-
-                callback?.(err);
             } catch (e) {
                 logger.error("Exception in error handler!", e.stack || err);
             }
@@ -4110,7 +4046,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         return this.http.authedRequest<ISendEventResponse>(
-            undefined, Method.Put, path, undefined, event.getWireContent(),
+            Method.Put, path, undefined, event.getWireContent(),
         ).then((res) => {
             logger.log(`Event sent to ${event.getRoomId()} with event id ${res.event_id}`);
             return res;
@@ -4120,11 +4056,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * @param {string} roomId
      * @param {string} eventId
-     * @param {string} [txnId]  transaction id. One will be made up if not
-     *    supplied.
-     * @param {object|module:client.callback} cbOrOpts
-     *    Options to pass on, may contain `reason`.
-     *    Can be callback for backwards compatibility. Deprecated
+     * @param {string} [txnId]  transaction id. One will be made up if not supplied.
+     * @param {IRedactOpts} opts Options to pass on, may contain `reason`.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4132,36 +4065,34 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         eventId: string,
         txnId?: string | undefined,
-        cbOrOpts?: Callback | IRedactOpts,
+        opts?: IRedactOpts,
     ): Promise<ISendEventResponse>;
     public redactEvent(
         roomId: string,
         threadId: string | null,
         eventId: string,
         txnId?: string | undefined,
-        cbOrOpts?: Callback | IRedactOpts,
+        opts?: IRedactOpts,
     ): Promise<ISendEventResponse>;
     public redactEvent(
         roomId: string,
         threadId: string | null,
         eventId?: string,
-        txnId?: string | Callback | IRedactOpts,
-        cbOrOpts?: Callback | IRedactOpts,
+        txnId?: string | IRedactOpts,
+        opts?: IRedactOpts,
     ): Promise<ISendEventResponse> {
         if (!eventId?.startsWith(EVENT_ID_PREFIX)) {
-            cbOrOpts = txnId as (Callback | IRedactOpts);
+            opts = txnId as IRedactOpts;
             txnId = eventId;
             eventId = threadId;
             threadId = null;
         }
-        const opts = typeof (cbOrOpts) === 'object' ? cbOrOpts : {};
-        const reason = opts.reason;
-        const callback = typeof (cbOrOpts) === 'function' ? cbOrOpts : undefined;
+        const reason = opts?.reason;
         return this.sendCompleteEvent(roomId, threadId, {
             type: EventType.RoomRedaction,
             content: { reason },
             redacts: eventId,
-        }, txnId as string, callback);
+        }, txnId as string);
     }
 
     /**
@@ -4169,7 +4100,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {Object} content
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to an ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4177,32 +4107,24 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         content: IContent,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendMessage(
         roomId: string,
         threadId: string | null,
         content: IContent,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendMessage(
         roomId: string,
         threadId: string | null | IContent,
         content: IContent | string,
-        txnId?: string | Callback,
-        callback?: Callback,
+        txnId?: string,
     ): Promise<ISendEventResponse> {
         if (typeof threadId !== "string" && threadId !== null) {
-            callback = txnId as Callback;
             txnId = content as string;
             content = threadId as IContent;
             threadId = null;
         }
-        if (utils.isFunction(txnId)) {
-            callback = txnId as any as Callback; // for legacy
-            txnId = undefined;
-        }
 
         // Populate all outbound events with Extensible Events metadata to ensure there's a
         // reasonably large pool of messages to parse.
@@ -4248,8 +4170,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             threadId as (string | null),
             eventType,
             sendContent,
-            txnId as string,
-            callback,
+            txnId,
         );
     }
 
@@ -4258,7 +4179,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {string} body
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4266,30 +4186,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendTextMessage(
         roomId: string,
         threadId: string | null,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendTextMessage(
         roomId: string,
         threadId: string | null,
         body: string,
-        txnId?: string | Callback,
-        callback?: Callback,
+        txnId?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = txnId as Callback;
             txnId = body;
             body = threadId;
             threadId = null;
         }
         const content = ContentHelpers.makeTextMessage(body);
-        return this.sendMessage(roomId, threadId, content, txnId as string, callback);
+        return this.sendMessage(roomId, threadId, content, txnId);
     }
 
     /**
@@ -4297,7 +4213,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {string} body
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4305,30 +4220,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendNotice(
         roomId: string,
         threadId: string | null,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendNotice(
         roomId: string,
         threadId: string | null,
         body: string,
-        txnId?: string | Callback,
-        callback?: Callback,
+        txnId?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = txnId as Callback;
             txnId = body;
             body = threadId;
             threadId = null;
         }
         const content = ContentHelpers.makeNotice(body);
-        return this.sendMessage(roomId, threadId, content, txnId as string, callback);
+        return this.sendMessage(roomId, threadId, content, txnId);
     }
 
     /**
@@ -4336,7 +4247,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {string} body
      * @param {string} txnId Optional.
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4344,30 +4254,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendEmoteMessage(
         roomId: string,
         threadId: string | null,
         body: string,
         txnId?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendEmoteMessage(
         roomId: string,
         threadId: string | null,
         body: string,
-        txnId?: string | Callback,
-        callback?: Callback,
+        txnId?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = txnId as Callback;
             txnId = body;
             body = threadId;
             threadId = null;
         }
         const content = ContentHelpers.makeEmoteMessage(body);
-        return this.sendMessage(roomId, threadId, content, txnId as string, callback);
+        return this.sendMessage(roomId, threadId, content, txnId);
     }
 
     /**
@@ -4376,7 +4282,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} url
      * @param {Object} info
      * @param {string} text
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4385,7 +4290,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         url: string,
         info?: IImageInfo,
         text?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendImageMessage(
         roomId: string,
@@ -4393,34 +4297,27 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         url: string,
         info?: IImageInfo,
         text?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendImageMessage(
         roomId: string,
         threadId: string | null,
         url: string | IImageInfo,
         info?: IImageInfo | string,
-        text: Callback | string = "Image",
-        callback?: Callback,
+        text = "Image",
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = text as Callback;
             text = info as string || "Image";
             info = url as IImageInfo;
             url = threadId as string;
             threadId = null;
         }
-        if (utils.isFunction(text)) {
-            callback = text as any as Callback; // legacy
-            text = undefined;
-        }
         const content = {
             msgtype: MsgType.Image,
             url: url,
             info: info,
             body: text,
         };
-        return this.sendMessage(roomId, threadId, content, undefined, callback);
+        return this.sendMessage(roomId, threadId, content);
     }
 
     /**
@@ -4429,7 +4326,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} url
      * @param {Object} info
      * @param {string} text
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4438,7 +4334,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         url: string,
         info?: IImageInfo,
         text?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendStickerMessage(
         roomId: string,
@@ -4446,34 +4341,27 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         url: string,
         info?: IImageInfo,
         text?: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendStickerMessage(
         roomId: string,
         threadId: string | null,
         url: string | IImageInfo,
         info?: IImageInfo | string,
-        text: Callback | string = "Sticker",
-        callback?: Callback,
+        text = "Sticker",
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = text as Callback;
             text = info as string || "Sticker";
             info = url as IImageInfo;
             url = threadId as string;
             threadId = null;
         }
-        if (utils.isFunction(text)) {
-            callback = text as any as Callback; // legacy
-            text = undefined;
-        }
         const content = {
             url: url,
             info: info,
             body: text,
         };
 
-        return this.sendEvent(roomId, threadId, EventType.Sticker, content, undefined, callback);
+        return this.sendEvent(roomId, threadId, EventType.Sticker, content);
     }
 
     /**
@@ -4481,7 +4369,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {string} body
      * @param {string} htmlBody
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4489,37 +4376,32 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlMessage(
         roomId: string,
         threadId: string | null,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlMessage(
         roomId: string,
         threadId: string | null,
         body: string,
-        htmlBody: string | Callback,
-        callback?: Callback,
+        htmlBody?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = htmlBody as Callback;
             htmlBody = body as string;
             body = threadId;
             threadId = null;
         }
-        const content = ContentHelpers.makeHtmlMessage(body, htmlBody as string);
-        return this.sendMessage(roomId, threadId, content, undefined, callback);
+        const content = ContentHelpers.makeHtmlMessage(body, htmlBody);
+        return this.sendMessage(roomId, threadId, content);
     }
 
     /**
      * @param {string} roomId
      * @param {string} body
      * @param {string} htmlBody
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4527,30 +4409,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlNotice(
         roomId: string,
         threadId: string | null,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlNotice(
         roomId: string,
         threadId: string | null,
         body: string,
-        htmlBody: string | Callback,
-        callback?: Callback,
+        htmlBody?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = htmlBody as Callback;
             htmlBody = body as string;
             body = threadId;
             threadId = null;
         }
-        const content = ContentHelpers.makeHtmlNotice(body, htmlBody as string);
-        return this.sendMessage(roomId, threadId, content, undefined, callback);
+        const content = ContentHelpers.makeHtmlNotice(body, htmlBody);
+        return this.sendMessage(roomId, threadId, content);
     }
 
     /**
@@ -4558,7 +4436,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} threadId
      * @param {string} body
      * @param {string} htmlBody
-     * @param {module:client.callback} callback Optional. Deprecated
      * @return {Promise} Resolves: to a ISendEventResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4566,30 +4443,26 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlEmote(
         roomId: string,
         threadId: string | null,
         body: string,
         htmlBody: string,
-        callback?: Callback,
     ): Promise<ISendEventResponse>;
     public sendHtmlEmote(
         roomId: string,
         threadId: string | null,
         body: string,
-        htmlBody: string | Callback,
-        callback?: Callback,
+        htmlBody?: string,
     ): Promise<ISendEventResponse> {
         if (!threadId?.startsWith(EVENT_ID_PREFIX) && threadId !== null) {
-            callback = htmlBody as Callback;
             htmlBody = body as string;
             body = threadId;
             threadId = null;
         }
-        const content = ContentHelpers.makeHtmlEmote(body, htmlBody as string);
-        return this.sendMessage(roomId, threadId, content, undefined, callback);
+        const content = ContentHelpers.makeHtmlEmote(body, htmlBody);
+        return this.sendMessage(roomId, threadId, content);
     }
 
     /**
@@ -4598,7 +4471,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {ReceiptType} receiptType The kind of receipt e.g. "m.read". Other than
      * ReceiptType.Read are experimental!
      * @param {object} body Additional content to send alongside the receipt.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -4606,13 +4478,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         event: MatrixEvent,
         receiptType: ReceiptType,
         body: any,
-        callback?: Callback,
     ): Promise<{}> {
-        if (typeof (body) === 'function') {
-            callback = body as any as Callback; // legacy
-            body = {};
-        }
-
         if (this.isGuest()) {
             return Promise.resolve({}); // guests cannot send receipts so don't bother.
         }
@@ -4631,7 +4497,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 : MAIN_ROOM_TIMELINE;
         }
 
-        const promise = this.http.authedRequest(callback, Method.Post, path, undefined, body || {});
+        const promise = this.http.authedRequest(Method.Post, path, undefined, body || {});
 
         const room = this.getRoom(event.getRoomId());
         if (room && this.credentials.userId) {
@@ -4644,14 +4510,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * Send a read receipt.
      * @param {Event} event The event that has been read.
      * @param {ReceiptType} receiptType other than ReceiptType.Read are experimental! Optional.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public async sendReadReceipt(
         event: MatrixEvent | null,
         receiptType = ReceiptType.Read,
-        callback?: Callback,
     ): Promise<{} | undefined> {
         if (!event) return;
         const eventId = event.getId();
@@ -4660,7 +4524,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             throw new Error(`Cannot set read receipt to a pending event (${eventId})`);
         }
 
-        return this.sendReceipt(event, receiptType, {}, callback);
+        return this.sendReceipt(event, receiptType, {});
     }
 
     /**
@@ -4721,12 +4585,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * describe (ms since epoch).  The preview returned will either be the most
      * recent one preceding this timestamp if available, or failing that the next
      * most recent available preview.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Object of OG metadata.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      * May return synthesized attributes if the URL lacked OG meta.
      */
-    public getUrlPreview(url: string, ts: number, callback?: Callback): Promise<IPreviewUrlResponse> {
+    public getUrlPreview(url: string, ts: number): Promise<IPreviewUrlResponse> {
         // bucket the timestamp to the nearest minute to prevent excessive spam to the server
         // Surely 60-second accuracy is enough for anyone.
         ts = Math.floor(ts / 60000) * 60000;
@@ -4740,20 +4603,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         // If there's already a request in flight (or we've handled it), return that instead.
         const cachedPreview = this.urlPreviewCache[key];
         if (cachedPreview) {
-            if (callback) {
-                cachedPreview.then(callback).catch(callback);
-            }
             return cachedPreview;
         }
 
-        const resp = this.http.authedRequest(
-            callback, Method.Get, "/preview_url", {
-                url,
-                ts: ts.toString(),
-            }, undefined, {
-                prefix: PREFIX_MEDIA_R0,
-            },
-        );
+        const resp = this.http.authedRequest<IPreviewUrlResponse>(Method.Get, "/preview_url", {
+            url,
+            ts: ts.toString(),
+        }, undefined, {
+            prefix: MediaPrefix.R0,
+        });
         // TODO: Expire the URL preview cache sometimes
         this.urlPreviewCache[key] = resp;
         return resp;
@@ -4763,11 +4621,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} roomId
      * @param {boolean} isTyping
      * @param {Number} timeoutMs
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public sendTyping(roomId: string, isTyping: boolean, timeoutMs: number, callback?: Callback): Promise<{}> {
+    public sendTyping(roomId: string, isTyping: boolean, timeoutMs: number): Promise<{}> {
         if (this.isGuest()) {
             return Promise.resolve({}); // guests cannot send typing notifications so don't bother.
         }
@@ -4782,7 +4639,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (isTyping) {
             data.timeout = timeoutMs ? timeoutMs : 20000;
         }
-        return this.http.authedRequest(callback, Method.Put, path, undefined, data);
+        return this.http.authedRequest(Method.Put, path, undefined, data);
     }
 
     /**
@@ -4866,25 +4723,23 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * @param {string} roomId
      * @param {string} userId
-     * @param {module:client.callback} callback Optional.
      * @param {string} reason Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public invite(roomId: string, userId: string, callback?: Callback, reason?: string): Promise<{}> {
-        return this.membershipChange(roomId, userId, "invite", reason, callback);
+    public invite(roomId: string, userId: string, reason?: string): Promise<{}> {
+        return this.membershipChange(roomId, userId, "invite", reason);
     }
 
     /**
      * Invite a user to a room based on their email address.
      * @param {string} roomId The room to invite the user to.
      * @param {string} email The email address to invite.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public inviteByEmail(roomId: string, email: string, callback?: Callback): Promise<{}> {
-        return this.inviteByThreePid(roomId, "email", email, callback);
+    public inviteByEmail(roomId: string, email: string): Promise<{}> {
+        return this.inviteByThreePid(roomId, "email", email);
     }
 
     /**
@@ -4892,11 +4747,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} roomId The room to invite the user to.
      * @param {string} medium The medium to invite the user e.g. "email".
      * @param {string} address The address for the specified medium.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async inviteByThreePid(roomId: string, medium: string, address: string, callback?: Callback): Promise<{}> {
+    public async inviteByThreePid(roomId: string, medium: string, address: string): Promise<{}> {
         const path = utils.encodeUri(
             "/rooms/$roomId/invite",
             { $roomId: roomId },
@@ -4925,17 +4779,16 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
         }
 
-        return this.http.authedRequest(callback, Method.Post, path, undefined, params);
+        return this.http.authedRequest(Method.Post, path, undefined, params);
     }
 
     /**
      * @param {string} roomId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public leave(roomId: string, callback?: Callback): Promise<{}> {
-        return this.membershipChange(roomId, undefined, "leave", undefined, callback);
+    public leave(roomId: string): Promise<{}> {
+        return this.membershipChange(roomId, undefined, "leave");
     }
 
     /**
@@ -4989,28 +4842,22 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} roomId
      * @param {string} userId
      * @param {string} reason Optional.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public ban(roomId: string, userId: string, reason?: string, callback?: Callback) {
-        return this.membershipChange(roomId, userId, "ban", reason, callback);
+    public ban(roomId: string, userId: string, reason?: string): Promise<{}> {
+        return this.membershipChange(roomId, userId, "ban", reason);
     }
 
     /**
      * @param {string} roomId
      * @param {boolean} deleteRoom True to delete the room from the store on success.
      * Default: true.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public forget(roomId: string, deleteRoom?: boolean, callback?: Callback): Promise<{}> {
-        if (deleteRoom === undefined) {
-            deleteRoom = true;
-        }
-        const promise = this.membershipChange(roomId, undefined, "forget", undefined,
-            callback);
+    public forget(roomId: string, deleteRoom = true): Promise<{}> {
+        const promise = this.membershipChange(roomId, undefined, "forget");
         if (!deleteRoom) {
             return promise;
         }
@@ -5024,11 +4871,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * @param {string} roomId
      * @param {string} userId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Object (currently empty)
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public unban(roomId: string, userId: string, callback?: Callback): Promise<void> {
+    public unban(roomId: string, userId: string): Promise<{}> {
         // unbanning != set their state to leave: this used to be
         // the case, but was then changed so that leaving was always
         // a revoking of privilege, otherwise two people racing to
@@ -5040,20 +4886,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const data = {
             user_id: userId,
         };
-        return this.http.authedRequest(
-            callback, Method.Post, path, undefined, data,
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, data);
     }
 
     /**
      * @param {string} roomId
      * @param {string} userId
      * @param {string} reason Optional.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public kick(roomId: string, userId: string, reason?: string, callback?: Callback): Promise<{}> {
+    public kick(roomId: string, userId: string, reason?: string): Promise<{}> {
         const path = utils.encodeUri("/rooms/$roomId/kick", {
             $roomId: roomId,
         });
@@ -5061,9 +4904,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             user_id: userId,
             reason: reason,
         };
-        return this.http.authedRequest(
-            callback, Method.Post, path, undefined, data,
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, data);
     }
 
     private membershipChange(
@@ -5071,19 +4912,13 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         userId: string,
         membership: string,
         reason?: string,
-        callback?: Callback,
     ): Promise<{}> { // API returns an empty object
-        if (utils.isFunction(reason)) {
-            callback = reason as any as Callback; // legacy
-            reason = undefined;
-        }
-
         const path = utils.encodeUri("/rooms/$room_id/$membership", {
             $room_id: roomId,
             $membership: membership,
         });
         return this.http.authedRequest(
-            callback, Method.Post, path, undefined, {
+            Method.Post, path, undefined, {
                 user_id: userId,  // may be undefined e.g. on leave
                 reason: reason,
             },
@@ -5108,29 +4943,27 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     /**
      * @param {string} info The kind of info to set (e.g. 'avatar_url')
      * @param {Object} data The JSON object to set.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     // eslint-disable-next-line camelcase
-    public setProfileInfo(info: "avatar_url", data: { avatar_url: string }, callback?: Callback): Promise<{}>;
-    public setProfileInfo(info: "displayname", data: { displayname: string }, callback?: Callback): Promise<{}>;
-    public setProfileInfo(info: "avatar_url" | "displayname", data: object, callback?: Callback): Promise<{}> {
+    public setProfileInfo(info: "avatar_url", data: { avatar_url: string }): Promise<{}>;
+    public setProfileInfo(info: "displayname", data: { displayname: string }): Promise<{}>;
+    public setProfileInfo(info: "avatar_url" | "displayname", data: object): Promise<{}> {
         const path = utils.encodeUri("/profile/$userId/$info", {
             $userId: this.credentials.userId,
             $info: info,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, data);
+        return this.http.authedRequest(Method.Put, path, undefined, data);
     }
 
     /**
      * @param {string} name
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async setDisplayName(name: string, callback?: Callback): Promise<{}> {
-        const prom = await this.setProfileInfo("displayname", { displayname: name }, callback);
+    public async setDisplayName(name: string): Promise<{}> {
+        const prom = await this.setProfileInfo("displayname", { displayname: name });
         // XXX: synthesise a profile update for ourselves because Synapse is broken and won't
         const user = this.getUser(this.getUserId());
         if (user) {
@@ -5142,12 +4975,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
     /**
      * @param {string} url
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: {} an empty object.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async setAvatarUrl(url: string, callback?: Callback): Promise<{}> {
-        const prom = await this.setProfileInfo("avatar_url", { avatar_url: url }, callback);
+    public async setAvatarUrl(url: string): Promise<{}> {
+        const prom = await this.setProfileInfo("avatar_url", { avatar_url: url });
         // XXX: synthesise a profile update for ourselves because Synapse is broken and won't
         const user = this.getUser(this.getUserId());
         if (user) {
@@ -5184,12 +5016,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {Object} opts Options to apply
      * @param {string} opts.presence One of "online", "offline" or "unavailable"
      * @param {string} opts.status_msg The status message to attach.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      * @throws If 'presence' isn't a valid presence enum value.
      */
-    public setPresence(opts: IPresenceOpts, callback?: Callback): Promise<void> {
+    public async setPresence(opts: IPresenceOpts): Promise<void> {
         const path = utils.encodeUri("/presence/$userId/status", {
             $userId: this.credentials.userId,
         });
@@ -5202,23 +5033,20 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (validStates.indexOf(opts.presence) === -1) {
             throw new Error("Bad presence value: " + opts.presence);
         }
-        return this.http.authedRequest(
-            callback, Method.Put, path, undefined, opts,
-        );
+        await this.http.authedRequest(Method.Put, path, undefined, opts);
     }
 
     /**
      * @param {string} userId The user to get presence for
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: The presence state for this user.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public getPresence(userId: string, callback?: Callback): Promise<IStatusResponse> {
+    public getPresence(userId: string): Promise<IStatusResponse> {
         const path = utils.encodeUri("/presence/$userId/status", {
             $userId: userId,
         });
 
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -5232,17 +5060,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {Room} room The room to get older messages in.
      * @param {number} limit Optional. The maximum number of previous events to
      * pull in. Default: 30.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Room. If you are at the beginning
      * of the timeline, <code>Room.oldState.paginationToken</code> will be
      * <code>null</code>.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public scrollback(room: Room, limit = 30, callback?: Callback): Promise<Room> {
-        if (utils.isFunction(limit)) {
-            callback = limit as any as Callback; // legacy
-            limit = undefined;
-        }
+    public scrollback(room: Room, limit = 30): Promise<Room> {
         let timeToWaitMs = 0;
 
         let info = this.ongoingScrollbacks[room.roomId] || {};
@@ -5294,13 +5117,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 }
                 this.store.storeEvents(room, matrixEvents, res.end, true);
                 this.ongoingScrollbacks[room.roomId] = null;
-                callback?.(null, room);
                 resolve(room);
             }).catch((err) => {
                 this.ongoingScrollbacks[room.roomId] = {
                     errorTs: Date.now(),
                 };
-                callback?.(err);
                 reject(err);
             });
         });
@@ -5367,7 +5188,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         // TODO: we should implement a backoff (as per scrollback()) to deal more nicely with HTTP errors.
-        const res = await this.http.authedRequest<IContextResponse>(undefined, Method.Get, path, params);
+        const res = await this.http.authedRequest<IContextResponse>(Method.Get, path, params);
         if (!res.event) {
             throw new Error("'event' not in '/context' result - homeserver too old?");
         }
@@ -5538,7 +5359,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (filter) {
             params.filter = JSON.stringify(filter);
         }
-        return this.http.authedRequest(undefined, Method.Get, path, params);
+        return this.http.authedRequest(Method.Get, path, params);
     }
 
     /**
@@ -5599,7 +5420,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             opts.prefix = "/_matrix/client/unstable/org.matrix.msc3856";
         }
 
-        return this.http.authedRequest<IThreadedMessagesResponse>(undefined, Method.Get, path, params, undefined, opts)
+        return this.http.authedRequest<IThreadedMessagesResponse>(Method.Get, path, params, undefined, opts)
             .then(res => ({
                 ...res,
                 start: res.prev_batch,
@@ -5662,7 +5483,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
 
             promise = this.http.authedRequest<INotificationsResponse>(
-                undefined, Method.Get, path, params,
+                Method.Get, path, params,
             ).then(async (res) => {
                 const token = res.next_token;
                 const matrixEvents: MatrixEvent[] = [];
@@ -6007,7 +5828,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} clientSecret As requestEmailToken
      * @param {number} sendAttempt As requestEmailToken
      * @param {string} nextLink As requestEmailToken
-     * @param {module:client.callback} callback Optional. As requestEmailToken
      * @return {Promise} Resolves: As requestEmailToken
      */
     public requestPasswordEmailToken(
@@ -6087,7 +5907,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
         }
 
-        return this.http.request(undefined, Method.Post, endpoint, undefined, postParams);
+        return this.http.request(Method.Post, endpoint, undefined, postParams);
     }
 
     /**
@@ -6189,7 +6009,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
     }
 
-    public searchMessageText(opts: ISearchOpts, callback?: Callback): Promise<ISearchResponse> {
+    public searchMessageText(opts: ISearchOpts): Promise<ISearchResponse> {
         const roomEvents: ISearchRequestBody["search_categories"]["room_events"] = {
             search_term: opts.query,
         };
@@ -6204,7 +6024,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                     room_events: roomEvents,
                 },
             },
-        }, callback);
+        });
     }
 
     /**
@@ -6371,7 +6191,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const path = utils.encodeUri("/user/$userId/filter", {
             $userId: this.credentials.userId,
         });
-        return this.http.authedRequest<IFilterResponse>(undefined, Method.Post, path, undefined, content)
+        return this.http.authedRequest<IFilterResponse>(Method.Post, path, undefined, content)
             .then((response) => {
                 // persist the filter
                 const filter = Filter.fromJson(this.credentials.userId, response.filter_id, content);
@@ -6402,7 +6222,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $filterId: filterId,
         });
 
-        return this.http.authedRequest<IFilterDefinition>(undefined, Method.Get, path).then((response) => {
+        return this.http.authedRequest<IFilterDefinition>(Method.Get, path).then((response) => {
             // persist the filter
             const filter = Filter.fromJson(userId, filterId, response);
             this.store.storeFilter(filter);
@@ -6477,9 +6297,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $userId: this.credentials.userId,
         });
 
-        return this.http.authedRequest(
-            undefined, Method.Post, path, undefined, {},
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, {});
     }
 
     private startCallEventHandler = (): void => {
@@ -6490,12 +6308,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     };
 
     /**
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: ITurnServerResponse object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public turnServer(callback?: Callback): Promise<ITurnServerResponse> {
-        return this.http.authedRequest(callback, Method.Get, "/voip/turnServer");
+    public turnServer(): Promise<ITurnServerResponse> {
+        return this.http.authedRequest(Method.Get, "/voip/turnServer");
     }
 
     /**
@@ -6601,7 +6418,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             { $userId: this.getUserId() },
         );
         return this.http.authedRequest(
-            undefined, Method.Get, path, undefined, undefined, { prefix: '' },
+            Method.Get, path, undefined, undefined, { prefix: '' },
         ).then(r => r['admin']); // pull out the specific boolean we want
     }
 
@@ -6617,7 +6434,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             "/_synapse/admin/v1/whois/$userId",
             { $userId: userId },
         );
-        return this.http.authedRequest(undefined, Method.Get, path, undefined, undefined, { prefix: '' });
+        return this.http.authedRequest(Method.Get, path, undefined, undefined, { prefix: '' });
     }
 
     /**
@@ -6631,9 +6448,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             "/_synapse/admin/v1/deactivate/$userId",
             { $userId: userId },
         );
-        return this.http.authedRequest(
-            undefined, Method.Post, path, undefined, undefined, { prefix: '' },
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, undefined, { prefix: '' });
     }
 
     private async fetchClientWellKnown(): Promise<void> {
@@ -6692,8 +6507,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         );
 
         const res = await this.http.authedRequest<{ joined: string[] }>(
-            undefined, Method.Get, path, undefined, undefined,
-            { prefix: PREFIX_UNSTABLE },
+            Method.Get, path, undefined, undefined,
+            { prefix: ClientPrefix.Unstable },
         );
         return res.joined;
     }
@@ -6709,7 +6524,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         this.serverVersionsPromise = this.http.request<IServerVersions>(
-            undefined, // callback
             Method.Get, "/_matrix/client/versions",
             undefined, // queryParams
             undefined, // data
@@ -6997,12 +6811,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
     }
 
-    private termsUrlForService(serviceType: SERVICE_TYPES, baseUrl: string) {
+    private termsUrlForService(serviceType: SERVICE_TYPES, baseUrl: string): URL {
         switch (serviceType) {
             case SERVICE_TYPES.IS:
-                return baseUrl + PREFIX_IDENTITY_V2 + '/terms';
+                return this.http.getUrl("/terms", undefined, IdentityPrefix.V2, baseUrl);
             case SERVICE_TYPES.IM:
-                return baseUrl + '/_matrix/integrations/v1/terms';
+                return this.http.getUrl("/terms", undefined, "/_matrix/integrations/v1", baseUrl);
             default:
                 throw new Error('Unsupported service type');
         }
@@ -7078,7 +6892,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public isUsernameAvailable(username: string): Promise<boolean> {
         return this.http.authedRequest<{ available: true }>(
-            undefined, Method.Get, '/register/available', { username },
+            Method.Get, '/register/available', { username },
         ).then((response) => {
             return response.available;
         }).catch(response => {
@@ -7099,7 +6913,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *     true to bind msisdn.
      * @param {string} guestAccessToken
      * @param {string} inhibitLogin
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -7111,7 +6924,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         bindThreepids?: boolean | null | { email?: boolean, msisdn?: boolean },
         guestAccessToken?: string,
         inhibitLogin?: boolean,
-        callback?: Callback,
     ): Promise<IAuthData> {
         // backwards compat
         if (bindThreepids === true) {
@@ -7119,11 +6931,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         } else if (bindThreepids === null || bindThreepids === undefined || bindThreepids === false) {
             bindThreepids = {};
         }
-        if (typeof inhibitLogin === 'function') {
-            callback = inhibitLogin;
-            inhibitLogin = undefined;
-        }
-
         if (sessionId) {
             auth.session = sessionId;
         }
@@ -7160,7 +6967,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             params.x_show_msisdn = true;
         }
 
-        return this.registerRequest(params, undefined, callback);
+        return this.registerRequest(params);
     }
 
     /**
@@ -7181,31 +6988,29 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *
      * @param {Object=} opts Registration options
      * @param {Object} opts.body JSON HTTP body to provide.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: JSON object that contains:
      *                   { user_id, device_id, access_token, home_server }
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public registerGuest(opts: { body?: any }, callback?: Callback): Promise<any> { // TODO: Types
+    public registerGuest(opts: { body?: any }): Promise<any> { // TODO: Types
         opts = opts || {};
         opts.body = opts.body || {};
-        return this.registerRequest(opts.body, "guest", callback);
+        return this.registerRequest(opts.body, "guest");
     }
 
     /**
      * @param {Object} data   parameters for registration request
      * @param {string=} kind  type of user to register. may be "guest"
-     * @param {module:client.callback=} callback
      * @return {Promise} Resolves: to the /register response
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public registerRequest(data: IRegisterRequestParams, kind?: string, callback?: Callback): Promise<IAuthData> {
+    public registerRequest(data: IRegisterRequestParams, kind?: string): Promise<IAuthData> {
         const params: { kind?: string } = {};
         if (kind) {
             params.kind = kind;
         }
 
-        return this.http.request(callback, Method.Post, "/register", params, data);
+        return this.http.request(Method.Post, "/register", params, data);
     }
 
     /**
@@ -7221,35 +7026,32 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public refreshToken(refreshToken: string): Promise<IRefreshTokenResponse> {
         return this.http.authedRequest(
-            undefined,
             Method.Post,
             "/refresh",
             undefined,
             { refresh_token: refreshToken },
             {
-                prefix: PREFIX_V1,
+                prefix: ClientPrefix.V1,
                 inhibitLogoutEmit: true, // we don't want to cause logout loops
             },
         );
     }
 
     /**
-     * @param {module:client.callback} callback Optional.
      * @return {Promise<ILoginFlowsResponse>} Resolves to the available login flows
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public loginFlows(callback?: Callback): Promise<ILoginFlowsResponse> {
-        return this.http.request(callback, Method.Get, "/login");
+    public loginFlows(): Promise<ILoginFlowsResponse> {
+        return this.http.request(Method.Get, "/login");
     }
 
     /**
      * @param {string} loginType
      * @param {Object} data
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public login(loginType: string, data: any, callback?: Callback): Promise<any> { // TODO: Types
+    public login(loginType: string, data: any): Promise<any> { // TODO: Types
         const loginData = {
             type: loginType,
         };
@@ -7257,46 +7059,42 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         // merge data into loginData
         Object.assign(loginData, data);
 
-        return this.http.authedRequest(
-            (error, response) => {
-                if (response && response.access_token && response.user_id) {
-                    this.http.opts.accessToken = response.access_token;
-                    this.credentials = {
-                        userId: response.user_id,
-                    };
-                }
-
-                if (callback) {
-                    callback(error, response);
-                }
-            }, Method.Post, "/login", undefined, loginData,
-        );
+        return this.http.authedRequest<{
+            access_token?: string;
+            user_id?: string;
+        }>(Method.Post, "/login", undefined, loginData).then(response => {
+            if (response.access_token && response.user_id) {
+                this.http.opts.accessToken = response.access_token;
+                this.credentials = {
+                    userId: response.user_id,
+                };
+            }
+            return response;
+        });
     }
 
     /**
      * @param {string} user
      * @param {string} password
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public loginWithPassword(user: string, password: string, callback?: Callback): Promise<any> { // TODO: Types
+    public loginWithPassword(user: string, password: string): Promise<any> { // TODO: Types
         return this.login("m.login.password", {
             user: user,
             password: password,
-        }, callback);
+        });
     }
 
     /**
      * @param {string} relayState URL Callback after SAML2 Authentication
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public loginWithSAML2(relayState: string, callback?: Callback): Promise<any> { // TODO: Types
+    public loginWithSAML2(relayState: string): Promise<any> { // TODO: Types
         return this.login("m.login.saml2", {
             relay_state: relayState,
-        }, callback);
+        });
     }
 
     /**
@@ -7333,19 +7131,18 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             [SSO_ACTION_PARAM.unstable!]: action,
         };
 
-        return this.http.getUrl(url, params, PREFIX_R0);
+        return this.http.getUrl(url, params, ClientPrefix.R0).href;
     }
 
     /**
      * @param {string} token Login token previously received from homeserver
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public loginWithToken(token: string, callback?: Callback): Promise<any> { // TODO: Types
+    public loginWithToken(token: string): Promise<any> { // TODO: Types
         return this.login("m.login.token", {
             token: token,
-        }, callback);
+        });
     }
 
     /**
@@ -7354,11 +7151,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * method is called. The state of the MatrixClient object is not affected:
      * it is up to the caller to either reset or destroy the MatrixClient after
      * this method succeeds.
-     * @param {module:client.callback} callback Optional.
      * @param {boolean} stopClient whether to stop the client before calling /logout to prevent invalid token errors.
      * @return {Promise} Resolves: On success, the empty object {}
      */
-    public async logout(callback?: Callback, stopClient = false): Promise<{}> {
+    public async logout(stopClient = false): Promise<{}> {
         if (this.crypto?.backupManager?.getKeyBackupEnabled()) {
             try {
                 while (await this.crypto.backupManager.backupPendingKeys(200) > 0);
@@ -7372,11 +7168,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
         if (stopClient) {
             this.stopClient();
+            this.http.abort();
         }
 
-        return this.http.authedRequest(
-            callback, Method.Post, '/logout',
-        );
+        return this.http.authedRequest(Method.Post, '/logout');
     }
 
     /**
@@ -7392,10 +7187,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @return {Promise} Resolves: On success, the empty object
      */
     public deactivateAccount(auth?: any, erase?: boolean): Promise<{}> {
-        if (typeof (erase) === 'function') {
-            throw new Error('deactivateAccount no longer accepts a callback parameter');
-        }
-
         const body: any = {};
         if (auth) {
             body.auth = auth;
@@ -7404,7 +7195,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             body.erase = erase;
         }
 
-        return this.http.authedRequest(undefined, Method.Post, '/account/deactivate', undefined, body);
+        return this.http.authedRequest(Method.Post, '/account/deactivate', undefined, body);
     }
 
     /**
@@ -7419,12 +7210,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     public requestLoginToken(auth?: IAuthData): Promise<UIAResponse<LoginTokenPostResponse>> {
         const body: UIARequest<{}> = { auth };
         return this.http.authedRequest(
-            undefined, // no callback support
             Method.Post,
             "/org.matrix.msc3882/login/token",
             undefined, // no query params
             body,
-            { prefix: PREFIX_UNSTABLE },
+            { prefix: ClientPrefix.Unstable },
         );
     }
 
@@ -7443,7 +7233,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
         return this.http.getUrl(path, {
             session: authSessionId,
-        }, PREFIX_R0);
+        }, ClientPrefix.R0).href;
     }
 
     /**
@@ -7455,14 +7245,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string[]} options.invite A list of user IDs to invite to this room.
      * @param {string} options.name The name to give this room.
      * @param {string} options.topic The topic to give this room.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: <code>{room_id: {string}}</code>
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async createRoom(
-        options: ICreateRoomOpts,
-        callback?: Callback,
-    ): Promise<{ room_id: string }> { // eslint-disable-line camelcase
+    public async createRoom(options: ICreateRoomOpts): Promise<{ room_id: string }> { // eslint-disable-line camelcase
         // some valid options include: room_alias_name, visibility, invite
 
         // inject the id_access_token if inviting 3rd party addresses
@@ -7481,7 +7267,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             }
         }
 
-        return this.http.authedRequest(callback, Method.Post, "/createRoom", undefined, options);
+        return this.http.authedRequest(Method.Post, "/createRoom", undefined, options);
     }
 
     /**
@@ -7522,44 +7308,38 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 $eventType: eventType,
             });
         return this.http.authedRequest(
-            undefined, Method.Get, path, undefined, undefined, {
-                prefix: PREFIX_UNSTABLE,
+            Method.Get, path, undefined, undefined, {
+                prefix: ClientPrefix.Unstable,
             },
         );
     }
 
     /**
      * @param {string} roomId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public roomState(roomId: string, callback?: Callback): Promise<IStateEventWithRoomId[]> {
+    public roomState(roomId: string): Promise<IStateEventWithRoomId[]> {
         const path = utils.encodeUri("/rooms/$roomId/state", { $roomId: roomId });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
      * Get an event in a room by its event id.
      * @param {string} roomId
      * @param {string} eventId
-     * @param {module:client.callback} callback Optional.
      *
      * @return {Promise} Resolves to an object containing the event.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public fetchRoomEvent(
-        roomId: string,
-        eventId: string,
-        callback?: Callback,
-    ): Promise<IMinimalEvent> {
+    public fetchRoomEvent(roomId: string, eventId: string): Promise<IMinimalEvent> {
         const path = utils.encodeUri(
             "/rooms/$roomId/event/$eventId", {
                 $roomId: roomId,
                 $eventId: eventId,
             },
         );
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7567,7 +7347,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} includeMembership the membership type to include in the response
      * @param {string} excludeMembership the membership type to exclude from the response
      * @param {string} atEventId the id of the event for which moment in the timeline the members should be returned for
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: dictionary of userid to profile information
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -7576,7 +7355,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         includeMembership?: string,
         excludeMembership?: string,
         atEventId?: string,
-        callback?: Callback,
     ): Promise<{ [userId: string]: IStateEventWithRoomId[] }> {
         const queryParams: Record<string, string> = {};
         if (includeMembership) {
@@ -7593,7 +7371,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
         const path = utils.encodeUri("/rooms/$roomId/members?" + queryString,
             { $roomId: roomId });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7608,9 +7386,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         newVersion: string,
     ): Promise<{ replacement_room: string }> { // eslint-disable-line camelcase
         const path = utils.encodeUri("/rooms/$roomId/upgrade", { $roomId: roomId });
-        return this.http.authedRequest(
-            undefined, Method.Post, path, undefined, { new_version: newVersion },
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, { new_version: newVersion });
     }
 
     /**
@@ -7618,7 +7394,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} roomId
      * @param {string} eventType
      * @param {string} stateKey
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -7626,7 +7401,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         roomId: string,
         eventType: string,
         stateKey: string,
-        callback?: Callback,
     ): Promise<Record<string, any>> {
         const pathParams = {
             $roomId: roomId,
@@ -7637,9 +7411,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (stateKey !== undefined) {
             path = utils.encodeUri(path + "/$stateKey", pathParams);
         }
-        return this.http.authedRequest(
-            callback, Method.Get, path,
-        );
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7647,7 +7419,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} eventType
      * @param {Object} content
      * @param {string} stateKey
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -7656,7 +7427,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         eventType: string,
         content: any,
         stateKey = "",
-        callback?: Callback,
     ): Promise<ISendEventResponse> {
         const pathParams = {
             $roomId: roomId,
@@ -7667,27 +7437,21 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (stateKey !== undefined) {
             path = utils.encodeUri(path + "/$stateKey", pathParams);
         }
-        return this.http.authedRequest(callback, Method.Put, path, undefined, content);
+        return this.http.authedRequest(Method.Put, path, undefined, content);
     }
 
     /**
      * @param {string} roomId
      * @param {Number} limit
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public roomInitialSync(roomId: string, limit: number, callback?: Callback): Promise<IRoomInitialSyncResponse> {
-        if (utils.isFunction(limit)) {
-            callback = limit as any as Callback; // legacy
-            limit = undefined;
-        }
-
+    public roomInitialSync(roomId: string, limit: number): Promise<IRoomInitialSyncResponse> {
         const path = utils.encodeUri("/rooms/$roomId/initialSync",
             { $roomId: roomId },
         );
 
-        return this.http.authedRequest(callback, Method.Get, path, { limit: limit?.toString() ?? "30" });
+        return this.http.authedRequest(Method.Get, path, { limit: limit?.toString() ?? "30" });
     }
 
     /**
@@ -7726,7 +7490,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             content[ReceiptType.ReadPrivate] = rpEventId;
         }
 
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, content);
+        return this.http.authedRequest(Method.Post, path, undefined, content);
     }
 
     /**
@@ -7735,7 +7499,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public getJoinedRooms(): Promise<IJoinedRoomsResponse> {
         const path = utils.encodeUri("/joined_rooms", {});
-        return this.http.authedRequest(undefined, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7749,7 +7513,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const path = utils.encodeUri("/rooms/$roomId/joined_members", {
             $roomId: roomId,
         });
-        return this.http.authedRequest(undefined, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7761,29 +7525,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} options.since Token to paginate from
      * @param {object} options.filter Filter parameters
      * @param {string} options.filter.generic_search_term String to search for
-     * @param {module:client.callback} callback Optional.
-     * @return {Promise} Resolves: TODO
+     * @return {Promise} Resolves: IPublicRoomsResponse
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public publicRooms(options: IRoomDirectoryOptions, callback?: Callback): Promise<IPublicRoomsResponse> {
-        if (typeof (options) == 'function') {
-            callback = options;
-            options = {};
-        }
-        if (options === undefined) {
-            options = {};
-        }
-
-        const queryParams: any = {};
-        if (options.server) {
-            queryParams.server = options.server;
-            delete options.server;
-        }
-
-        if (Object.keys(options).length === 0 && Object.keys(queryParams).length === 0) {
-            return this.http.authedRequest(callback, Method.Get, "/publicRooms");
+    public publicRooms(
+        { server, limit, since, ...options }: IRoomDirectoryOptions = {},
+    ): Promise<IPublicRoomsResponse> {
+        const queryParams: QueryDict = { server, limit, since };
+        if (Object.keys(options).length === 0) {
+            return this.http.authedRequest(Method.Get, "/publicRooms", queryParams);
         } else {
-            return this.http.authedRequest(callback, Method.Post, "/publicRooms", queryParams, options);
+            return this.http.authedRequest(Method.Post, "/publicRooms", queryParams, options);
         }
     }
 
@@ -7791,33 +7543,31 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * Create an alias to room ID mapping.
      * @param {string} alias The room alias to create.
      * @param {string} roomId The room ID to link the alias to.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public createAlias(alias: string, roomId: string, callback?: Callback): Promise<{}> {
+    public createAlias(alias: string, roomId: string): Promise<{}> {
         const path = utils.encodeUri("/directory/room/$alias", {
             $alias: alias,
         });
         const data = {
             room_id: roomId,
         };
-        return this.http.authedRequest(callback, Method.Put, path, undefined, data);
+        return this.http.authedRequest(Method.Put, path, undefined, data);
     }
 
     /**
      * Delete an alias to room ID mapping. This alias must be on your local server,
      * and you must have sufficient access to do this operation.
      * @param {string} alias The room alias to delete.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: an empty object {}.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public deleteAlias(alias: string, callback?: Callback): Promise<{}> {
+    public deleteAlias(alias: string): Promise<{}> {
         const path = utils.encodeUri("/directory/room/$alias", {
             $alias: alias,
         });
-        return this.http.authedRequest(callback, Method.Delete, path);
+        return this.http.authedRequest(Method.Delete, path);
     }
 
     /**
@@ -7829,53 +7579,49 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public getLocalAliases(roomId: string): Promise<{ aliases: string[] }> {
         const path = utils.encodeUri("/rooms/$roomId/aliases", { $roomId: roomId });
-        const prefix = PREFIX_V3;
-        return this.http.authedRequest(undefined, Method.Get, path, undefined, undefined, { prefix });
+        const prefix = ClientPrefix.V3;
+        return this.http.authedRequest(Method.Get, path, undefined, undefined, { prefix });
     }
 
     /**
      * Get room info for the given alias.
      * @param {string} alias The room alias to resolve.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Object with room_id and servers.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public getRoomIdForAlias(
         alias: string,
-        callback?: Callback,
     ): Promise<{ room_id: string, servers: string[] }> { // eslint-disable-line camelcase
         // TODO: deprecate this or resolveRoomAlias
         const path = utils.encodeUri("/directory/room/$alias", {
             $alias: alias,
         });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
      * @param {string} roomAlias
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Object with room_id and servers.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     // eslint-disable-next-line camelcase
-    public resolveRoomAlias(roomAlias: string, callback?: Callback): Promise<{ room_id: string, servers: string[] }> {
+    public resolveRoomAlias(roomAlias: string): Promise<{ room_id: string, servers: string[] }> {
         // TODO: deprecate this or getRoomIdForAlias
         const path = utils.encodeUri("/directory/room/$alias", { $alias: roomAlias });
-        return this.http.request(callback, Method.Get, path);
+        return this.http.request(Method.Get, path);
     }
 
     /**
      * Get the visibility of a room in the current HS's room directory
      * @param {string} roomId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public getRoomDirectoryVisibility(roomId: string, callback?: Callback): Promise<{ visibility: Visibility }> {
+    public getRoomDirectoryVisibility(roomId: string): Promise<{ visibility: Visibility }> {
         const path = utils.encodeUri("/directory/list/room/$roomId", {
             $roomId: roomId,
         });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -7884,15 +7630,14 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} visibility "public" to make the room visible
      *                 in the public directory, or "private" to make
      *                 it invisible.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setRoomDirectoryVisibility(roomId: string, visibility: Visibility, callback?: Callback): Promise<{}> {
+    public setRoomDirectoryVisibility(roomId: string, visibility: Visibility): Promise<{}> {
         const path = utils.encodeUri("/directory/list/room/$roomId", {
             $roomId: roomId,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, { visibility });
+        return this.http.authedRequest(Method.Put, path, undefined, { visibility });
     }
 
     /**
@@ -7904,7 +7649,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} visibility "public" to make the room visible
      *                 in the public directory, or "private" to make
      *                 it invisible.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: result object
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -7912,15 +7656,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         networkId: string,
         roomId: string,
         visibility: "public" | "private",
-        callback?: Callback,
     ): Promise<any> { // TODO: Types
         const path = utils.encodeUri("/directory/list/appservice/$networkId/$roomId", {
             $networkId: networkId,
             $roomId: roomId,
         });
-        return this.http.authedRequest(
-            callback, Method.Put, path, undefined, { "visibility": visibility },
-        );
+        return this.http.authedRequest(Method.Put, path, undefined, { "visibility": visibility });
     }
 
     /**
@@ -7940,7 +7681,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             body.limit = opts.limit;
         }
 
-        return this.http.authedRequest(undefined, Method.Post, "/user_directory/search", undefined, body);
+        return this.http.authedRequest(Method.Post, "/user_directory/search", undefined, body);
     }
 
     /**
@@ -7971,10 +7712,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *   where it defaults to true for backwards compatibility). Ignored if
      *   opts.rawResponse is true.
      *
-     * @param {Function=} opts.callback Deprecated. Optional. The callback to
-     *    invoke on success/failure. See the promise return values for more
-     *    information.
-     *
      * @param {Function=} opts.progressHandler Optional. Called when a chunk of
      *    data has been uploaded, with an object containing the fields `loaded`
      *    (number of bytes transferred) and `total` (total size, if known).
@@ -7983,20 +7720,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *    determined by this.opts.onlyData, opts.rawResponse, and
      *    opts.onlyContentUri.  Rejects with an error (usually a MatrixError).
      */
-    public uploadContent<O extends IUploadOpts>(
-        file: FileType,
-        opts?: O,
-    ): IAbortablePromise<UploadContentResponseType<O>> {
-        return this.http.uploadContent<O>(file, opts);
+    public uploadContent(file: FileType, opts?: UploadOpts): Promise<UploadResponse> {
+        return this.http.uploadContent(file, opts);
     }
 
     /**
      * Cancel a file upload in progress
-     * @param {Promise} promise The promise returned from uploadContent
+     * @param {Promise} upload The object returned from uploadContent
      * @return {boolean} true if canceled, otherwise false
      */
-    public cancelUpload(promise: IAbortablePromise<any>): boolean {
-        return this.http.cancelUpload(promise);
+    public cancelUpload(upload: Promise<UploadResponse>): boolean {
+        return this.http.cancelUpload(upload);
     }
 
     /**
@@ -8007,7 +7741,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *  - loaded: Number of bytes uploaded
      *  - total: Total number of bytes to upload
      */
-    public getCurrentUploads(): IUpload[] {
+    public getCurrentUploads(): Upload[] {
         return this.http.getCurrentUploads();
     }
 
@@ -8015,36 +7749,28 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} userId
      * @param {string} info The kind of info to retrieve (e.g. 'displayname',
      * 'avatar_url').
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public getProfileInfo(
         userId: string,
         info?: string,
-        callback?: Callback,
         // eslint-disable-next-line camelcase
     ): Promise<{ avatar_url?: string, displayname?: string }> {
-        if (utils.isFunction(info)) {
-            callback = info as any as Callback; // legacy
-            info = undefined;
-        }
-
         const path = info ?
             utils.encodeUri("/profile/$userId/$info",
                 { $userId: userId, $info: info }) :
             utils.encodeUri("/profile/$userId",
                 { $userId: userId });
-        return this.http.authedRequest(callback, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves to a list of the user's threepids.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public getThreePids(callback?: Callback): Promise<{ threepids: IThreepid[] }> {
-        return this.http.authedRequest(callback, Method.Get, "/account/3pid");
+    public getThreePids(): Promise<{ threepids: IThreepid[] }> {
+        return this.http.authedRequest(Method.Get, "/account/3pid");
     }
 
     /**
@@ -8056,19 +7782,16 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *
      * @param {Object} creds
      * @param {boolean} bind
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: on success
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public addThreePid(creds: any, bind: boolean, callback?: Callback): Promise<any> { // TODO: Types
+    public addThreePid(creds: any, bind: boolean): Promise<any> { // TODO: Types
         const path = "/account/3pid";
         const data = {
             'threePidCreds': creds,
             'bind': bind,
         };
-        return this.http.authedRequest(
-            callback, Method.Post, path, undefined, data,
-        );
+        return this.http.authedRequest(Method.Post, path, undefined, data);
     }
 
     /**
@@ -8085,8 +7808,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public async addThreePidOnly(data: IAddThreePidOnlyBody): Promise<{}> {
         const path = "/account/3pid/add";
-        const prefix = await this.isVersionSupported("r0.6.0") ? PREFIX_R0 : PREFIX_UNSTABLE;
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, data, { prefix });
+        const prefix = await this.isVersionSupported("r0.6.0") ? ClientPrefix.R0 : ClientPrefix.Unstable;
+        return this.http.authedRequest(Method.Post, path, undefined, data, { prefix });
     }
 
     /**
@@ -8105,11 +7828,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public async bindThreePid(data: IBindThreePidBody): Promise<{}> {
         const path = "/account/3pid/bind";
-        const prefix = await this.isVersionSupported("r0.6.0") ?
-            PREFIX_R0 : PREFIX_UNSTABLE;
-        return this.http.authedRequest(
-            undefined, Method.Post, path, undefined, data, { prefix },
-        );
+        const prefix = await this.isVersionSupported("r0.6.0") ? ClientPrefix.R0 : ClientPrefix.Unstable;
+        return this.http.authedRequest(Method.Post, path, undefined, data, { prefix });
     }
 
     /**
@@ -8134,8 +7854,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             address,
             id_server: this.getIdentityServerUrl(true),
         };
-        const prefix = await this.isVersionSupported("r0.6.0") ? PREFIX_R0 : PREFIX_UNSTABLE;
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, data, { prefix });
+        const prefix = await this.isVersionSupported("r0.6.0") ? ClientPrefix.R0 : ClientPrefix.Unstable;
+        return this.http.authedRequest(Method.Post, path, undefined, data, { prefix });
     }
 
     /**
@@ -8152,7 +7872,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         // eslint-disable-next-line camelcase
     ): Promise<{ id_server_unbind_result: IdServerUnbindResult }> {
         const path = "/account/3pid/delete";
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, { medium, address });
+        return this.http.authedRequest(Method.Post, path, undefined, { medium, address });
     }
 
     /**
@@ -8160,36 +7880,14 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {Object} authDict
      * @param {string} newPassword The new desired password.
      * @param {boolean} logoutDevices Should all sessions be logged out after the password change. Defaults to true.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public setPassword(
         authDict: any,
         newPassword: string,
-        callback?: Callback,
-    ): Promise<{}>;
-    public setPassword(
-        authDict: any,
-        newPassword: string,
-        logoutDevices: boolean,
-        callback?: Callback,
-    ): Promise<{}>;
-    public setPassword(
-        authDict: any,
-        newPassword: string,
-        logoutDevices?: Callback | boolean,
-        callback?: Callback,
+        logoutDevices?: boolean,
     ): Promise<{}> {
-        if (typeof logoutDevices === 'function') {
-            callback = logoutDevices;
-        }
-        if (typeof logoutDevices !== 'boolean') {
-            // Use backwards compatible behaviour of not specifying logout_devices
-            // This way it is left up to the server:
-            logoutDevices = undefined;
-        }
-
         const path = "/account/password";
         const data = {
             'auth': authDict,
@@ -8197,9 +7895,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             'logout_devices': logoutDevices,
         };
 
-        return this.http.authedRequest<{}>(
-            callback, Method.Post, path, undefined, data,
-        );
+        return this.http.authedRequest<{}>(Method.Post, path, undefined, data);
     }
 
     /**
@@ -8208,7 +7904,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public getDevices(): Promise<{ devices: IMyDevice[] }> {
-        return this.http.authedRequest(undefined, Method.Get, "/devices");
+        return this.http.authedRequest(Method.Get, "/devices");
     }
 
     /**
@@ -8221,7 +7917,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const path = utils.encodeUri("/devices/$device_id", {
             $device_id: deviceId,
         });
-        return this.http.authedRequest(undefined, Method.Get, path);
+        return this.http.authedRequest(Method.Get, path);
     }
 
     /**
@@ -8238,7 +7934,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $device_id: deviceId,
         });
 
-        return this.http.authedRequest(undefined, Method.Put, path, undefined, body);
+        return this.http.authedRequest(Method.Put, path, undefined, body);
     }
 
     /**
@@ -8260,7 +7956,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             body.auth = auth;
         }
 
-        return this.http.authedRequest(undefined, Method.Delete, path, undefined, body);
+        return this.http.authedRequest(Method.Delete, path, undefined, body);
     }
 
     /**
@@ -8279,18 +7975,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         const path = "/delete_devices";
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, body);
+        return this.http.authedRequest(Method.Post, path, undefined, body);
     }
 
     /**
      * Gets all pushers registered for the logged-in user
      *
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Array of objects representing pushers
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public async getPushers(callback?: Callback): Promise<{ pushers: IPusher[] }> {
-        const response = await this.http.authedRequest(callback, Method.Get, "/pushers");
+    public async getPushers(): Promise<{ pushers: IPusher[] }> {
+        const response = await this.http.authedRequest<{ pushers: IPusher[] }>(Method.Get, "/pushers");
 
         // Migration path for clients that connect to a homeserver that does not support
         // MSC3881 yet, see https://github.com/matrix-org/matrix-spec-proposals/blob/kerry/remote-push-toggle/proposals/3881-remote-push-notification-toggling.md#migration
@@ -8310,13 +8005,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * Adds a new pusher or updates an existing pusher
      *
      * @param {IPusherRequest} pusher Object representing a pusher
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: Empty json object on success
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public setPusher(pusher: IPusherRequest, callback?: Callback): Promise<{}> {
+    public setPusher(pusher: IPusherRequest): Promise<{}> {
         const path = "/pushers/set";
-        return this.http.authedRequest(callback, Method.Post, path, undefined, pusher);
+        return this.http.authedRequest(Method.Post, path, undefined, pusher);
     }
 
     /**
@@ -8336,12 +8030,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
 
     /**
      * Get the push rules for the account from the server.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves to the push rules.
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
-    public getPushRules(callback?: Callback): Promise<IPushRules> {
-        return this.http.authedRequest(callback, Method.Get, "/pushrules/").then((rules: IPushRules) => {
+    public getPushRules(): Promise<IPushRules> {
+        return this.http.authedRequest(Method.Get, "/pushrules/").then((rules: IPushRules) => {
             return PushProcessor.rewriteDefaultRules(rules);
         });
     }
@@ -8351,7 +8044,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} kind
      * @param {string} ruleId
      * @param {Object} body
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -8360,21 +8052,19 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         kind: PushRuleKind,
         ruleId: Exclude<string, RuleId>,
         body: Pick<IPushRule, "actions" | "conditions" | "pattern">,
-        callback?: Callback,
     ): Promise<{}> {
         // NB. Scope not uri encoded because devices need the '/'
         const path = utils.encodeUri("/pushrules/" + scope + "/$kind/$ruleId", {
             $kind: kind,
             $ruleId: ruleId,
         });
-        return this.http.authedRequest(callback, Method.Put, path, undefined, body);
+        return this.http.authedRequest(Method.Put, path, undefined, body);
     }
 
     /**
      * @param {string} scope
      * @param {string} kind
      * @param {string} ruleId
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -8382,14 +8072,13 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         scope: string,
         kind: PushRuleKind,
         ruleId: Exclude<string, RuleId>,
-        callback?: Callback,
     ): Promise<{}> {
         // NB. Scope not uri encoded because devices need the '/'
         const path = utils.encodeUri("/pushrules/" + scope + "/$kind/$ruleId", {
             $kind: kind,
             $ruleId: ruleId,
         });
-        return this.http.authedRequest(callback, Method.Delete, path);
+        return this.http.authedRequest(Method.Delete, path);
     }
 
     /**
@@ -8398,7 +8087,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} kind
      * @param {string} ruleId
      * @param {boolean} enabled
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -8407,15 +8095,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         kind: PushRuleKind,
         ruleId: RuleId | string,
         enabled: boolean,
-        callback?: Callback,
     ): Promise<{}> {
         const path = utils.encodeUri("/pushrules/" + scope + "/$kind/$ruleId/enabled", {
             $kind: kind,
             $ruleId: ruleId,
         });
-        return this.http.authedRequest(
-            callback, Method.Put, path, undefined, { "enabled": enabled },
-        );
+        return this.http.authedRequest(Method.Put, path, undefined, { "enabled": enabled });
     }
 
     /**
@@ -8424,7 +8109,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {string} kind
      * @param {string} ruleId
      * @param {array} actions
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: to an empty object {}
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
@@ -8433,15 +8117,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         kind: PushRuleKind,
         ruleId: RuleId | string,
         actions: PushRuleAction[],
-        callback?: Callback,
     ): Promise<{}> {
         const path = utils.encodeUri("/pushrules/" + scope + "/$kind/$ruleId/actions", {
             $kind: kind,
             $ruleId: ruleId,
         });
-        return this.http.authedRequest(
-            callback, Method.Put, path, undefined, { "actions": actions },
-        );
+        return this.http.authedRequest(Method.Put, path, undefined, { "actions": actions });
     }
 
     /**
@@ -8449,19 +8130,17 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {Object} opts
      * @param {string} opts.next_batch the batch token to pass in the query string
      * @param {Object} opts.body the JSON object to pass to the request body.
-     * @param {module:client.callback} callback Optional.
      * @return {Promise} Resolves: TODO
      * @return {module:http-api.MatrixError} Rejects: with an error response.
      */
     public search(
         opts: { body: ISearchRequestBody, next_batch?: string }, // eslint-disable-line camelcase
-        callback?: Callback,
     ): Promise<ISearchResponse> {
         const queryParams: any = {};
         if (opts.next_batch) {
             queryParams.next_batch = opts.next_batch;
         }
-        return this.http.authedRequest(callback, Method.Post, "/search", queryParams, opts.body);
+        return this.http.authedRequest(Method.Post, "/search", queryParams, opts.body);
     }
 
     /**
@@ -8472,24 +8151,21 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param {Object=} opts this method no longer takes any opts,
      *  used to take opts.device_id but this was not removed from the spec as a redundant parameter
      *
-     * @param {module:client.callback=} callback
-     *
      * @return {Promise} Resolves: result object. Rejects: with
      *     an error response ({@link module:http-api.MatrixError}).
      */
     public uploadKeysRequest(
         content: IUploadKeysRequest,
         opts?: void,
-        callback?: Callback,
     ): Promise<IKeysUploadResponse> {
-        return this.http.authedRequest(callback, Method.Post, "/keys/upload", undefined, content);
+        return this.http.authedRequest(Method.Post, "/keys/upload", undefined, content);
     }
 
     public uploadKeySignatures(content: KeySignatures): Promise<IUploadKeySignaturesResponse> {
         return this.http.authedRequest(
-            undefined, Method.Post, '/keys/signatures/upload', undefined,
+            Method.Post, '/keys/signatures/upload', undefined,
             content, {
-                prefix: PREFIX_UNSTABLE,
+                prefix: ClientPrefix.Unstable,
             },
         );
     }
@@ -8507,13 +8183,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @return {Promise} Resolves: result object. Rejects: with
      *     an error response ({@link module:http-api.MatrixError}).
      */
-    public downloadKeysForUsers(userIds: string[], opts: { token?: string }): Promise<IDownloadKeyResult> {
-        if (utils.isFunction(opts)) {
-            // opts used to be 'callback'.
-            throw new Error('downloadKeysForUsers no longer accepts a callback parameter');
-        }
-        opts = opts || {};
-
+    public downloadKeysForUsers(userIds: string[], opts: { token?: string } = {}): Promise<IDownloadKeyResult> {
         const content: any = {
             device_keys: {},
         };
@@ -8524,7 +8194,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             content.device_keys[u] = [];
         });
 
-        return this.http.authedRequest(undefined, Method.Post, "/keys/query", undefined, content);
+        return this.http.authedRequest(Method.Post, "/keys/query", undefined, content);
     }
 
     /**
@@ -8563,7 +8233,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             content.timeout = timeout;
         }
         const path = "/keys/claim";
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, content);
+        return this.http.authedRequest(Method.Post, path, undefined, content);
     }
 
     /**
@@ -8582,15 +8252,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             to: newToken,
         };
 
-        return this.http.authedRequest(undefined, Method.Get, "/keys/changes", qps);
+        return this.http.authedRequest(Method.Get, "/keys/changes", qps);
     }
 
     public uploadDeviceSigningKeys(auth?: IAuthData, keys?: CrossSigningKeys): Promise<{}> { // API returns empty object
         const data = Object.assign({}, keys);
         if (auth) Object.assign(data, { auth });
         return this.http.authedRequest(
-            undefined, Method.Post, "/keys/device_signing/upload", undefined, data, {
-                prefix: PREFIX_UNSTABLE,
+            Method.Post, "/keys/device_signing/upload", undefined, data, {
+                prefix: ClientPrefix.Unstable,
             },
         );
     }
@@ -8613,11 +8283,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             throw new Error("No identity server base URL set");
         }
 
-        const uri = this.idBaseUrl + PREFIX_IDENTITY_V2 + "/account/register";
-        return this.http.requestOtherUrl(
-            undefined, Method.Post, uri,
-            null, hsOpenIdToken,
-        );
+        const uri = this.http.getUrl("/account/register", undefined, IdentityPrefix.V2, this.idBaseUrl);
+        return this.http.requestOtherUrl(Method.Post, uri, null, hsOpenIdToken);
     }
 
     /**
@@ -8636,7 +8303,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *                 the sendAttempt param as was used in the previous request.
      * @param {string} nextLink Optional If specified, the client will be redirected
      *                 to this link after validation.
-     * @param {module:client.callback} callback Optional.
      * @param {string} identityAccessToken The `access_token` field of the identity
      * server `/account/register` response (see {@link registerWithIdentityServer}).
      *
@@ -8649,7 +8315,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         clientSecret: string,
         sendAttempt: number,
         nextLink: string,
-        callback?: Callback,
         identityAccessToken?: string,
     ): Promise<any> { // TODO: Types
         const params = {
@@ -8660,8 +8325,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         };
 
         return this.http.idServerRequest(
-            callback, Method.Post, "/validate/email/requestToken",
-            params, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Post, "/validate/email/requestToken",
+            params, IdentityPrefix.V2, identityAccessToken,
         );
     }
 
@@ -8684,7 +8349,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *                 the sendAttempt param as was used in the previous request.
      * @param {string} nextLink Optional If specified, the client will be redirected
      *                 to this link after validation.
-     * @param {module:client.callback} callback Optional.
      * @param {string} identityAccessToken The `access_token` field of the Identity
      * Server `/account/register` response (see {@link registerWithIdentityServer}).
      *
@@ -8698,7 +8362,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         clientSecret: string,
         sendAttempt: number,
         nextLink: string,
-        callback?: Callback,
         identityAccessToken?: string,
     ): Promise<any> { // TODO: Types
         const params = {
@@ -8710,8 +8373,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         };
 
         return this.http.idServerRequest(
-            callback, Method.Post, "/validate/msisdn/requestToken",
-            params, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Post, "/validate/msisdn/requestToken",
+            params, IdentityPrefix.V2, identityAccessToken,
         );
     }
 
@@ -8747,8 +8410,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         };
 
         return this.http.idServerRequest(
-            undefined, Method.Post, "/validate/msisdn/submitToken",
-            params, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Post, "/validate/msisdn/submitToken",
+            params, IdentityPrefix.V2, identityAccessToken,
         );
     }
 
@@ -8776,15 +8439,11 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         clientSecret: string,
         msisdnToken: string,
     ): Promise<any> { // TODO: Types
-        const params = {
-            sid: sid,
-            client_secret: clientSecret,
-            token: msisdnToken,
-        };
-
-        return this.http.requestOtherUrl(
-            undefined, Method.Post, url, undefined, params,
-        );
+        const u = new URL(url);
+        u.searchParams.set("sid", sid);
+        u.searchParams.set("client_secret", clientSecret);
+        u.searchParams.set("token", msisdnToken);
+        return this.http.requestOtherUrl(Method.Post, u);
     }
 
     /**
@@ -8795,8 +8454,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public getIdentityHashDetails(identityAccessToken: string): Promise<any> { // TODO: Types
         return this.http.idServerRequest(
-            undefined, Method.Get, "/hash_details",
-            null, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Get, "/hash_details",
+            null, IdentityPrefix.V2, identityAccessToken,
         );
     }
 
@@ -8864,8 +8523,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }
 
         const response = await this.http.idServerRequest(
-            undefined, Method.Post, "/lookup",
-            params, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Post, "/lookup",
+            params, IdentityPrefix.V2, identityAccessToken,
         );
 
         if (!response || !response['mappings']) return []; // no results
@@ -8889,7 +8548,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      *
      * @param {string} medium The medium of the threepid, eg. 'email'
      * @param {string} address The textual address of the threepid
-     * @param {module:client.callback} callback Optional.
      * @param {string} identityAccessToken The `access_token` field of the Identity
      * Server `/account/register` response (see {@link registerWithIdentityServer}).
      *
@@ -8901,7 +8559,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
     public async lookupThreePid(
         medium: string,
         address: string,
-        callback?: Callback,
         identityAccessToken?: string,
     ): Promise<any> { // TODO: Types
         // Note: we're using the V2 API by calling this function, but our
@@ -8912,7 +8569,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         );
         const result = response.find(p => p.address === address);
         if (!result) {
-            if (callback) callback(null, {});
             return {};
         }
 
@@ -8928,7 +8584,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             // signatures
         };
 
-        if (callback) callback(null, mapping);
         return mapping;
     }
 
@@ -8982,8 +8637,8 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public getIdentityAccount(identityAccessToken: string): Promise<any> { // TODO: Types
         return this.http.idServerRequest(
-            undefined, Method.Get, "/account",
-            undefined, PREFIX_IDENTITY_V2, identityAccessToken,
+            Method.Get, "/account",
+            undefined, IdentityPrefix.V2, identityAccessToken,
         );
     }
 
@@ -9020,7 +8675,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         }, {});
         logger.log(`PUT ${path}`, targets);
 
-        return this.http.authedRequest(undefined, Method.Put, path, undefined, body);
+        return this.http.authedRequest(Method.Put, path, undefined, body);
     }
 
     /**
@@ -9041,7 +8696,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public getThirdpartyProtocols(): Promise<{ [protocol: string]: IProtocol }> {
         return this.http.authedRequest<Record<string, IProtocol>>(
-            undefined, Method.Get, "/thirdparty/protocols",
+            Method.Get, "/thirdparty/protocols",
         ).then((response) => {
             // sanity check
             if (!response || typeof (response) !== 'object') {
@@ -9067,7 +8722,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $protocol: protocol,
         });
 
-        return this.http.authedRequest(undefined, Method.Get, path, params);
+        return this.http.authedRequest(Method.Get, path, params);
     }
 
     /**
@@ -9083,12 +8738,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $protocol: protocol,
         });
 
-        return this.http.authedRequest(undefined, Method.Get, path, params);
+        return this.http.authedRequest(Method.Get, path, params);
     }
 
     public getTerms(serviceType: SERVICE_TYPES, baseUrl: string): Promise<any> { // TODO: Types
         const url = this.termsUrlForService(serviceType, baseUrl);
-        return this.http.requestOtherUrl(undefined, Method.Get, url);
+        return this.http.requestOtherUrl(Method.Get, url);
     }
 
     public agreeToTerms(
@@ -9098,10 +8753,13 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         termsUrls: string[],
     ): Promise<any> { // TODO: Types
         const url = this.termsUrlForService(serviceType, baseUrl);
+        utils.encodeParams({
+            user_accepts: termsUrls,
+        }, url.searchParams);
         const headers = {
             Authorization: "Bearer " + accessToken,
         };
-        return this.http.requestOtherUrl(undefined, Method.Post, url, null, { user_accepts: termsUrls }, { headers });
+        return this.http.requestOtherUrl(Method.Post, url, null, { headers });
     }
 
     /**
@@ -9118,7 +8776,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             $eventId: eventId,
         });
 
-        return this.http.authedRequest(undefined, Method.Post, path, undefined, { score, reason });
+        return this.http.authedRequest(Method.Post, path, undefined, { score, reason });
     }
 
     /**
@@ -9149,12 +8807,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             limit: limit?.toString(),
         };
 
-        return this.http.authedRequest<IRoomHierarchy>(undefined, Method.Get, path, queryParams, undefined, {
-            prefix: PREFIX_V1,
+        return this.http.authedRequest<IRoomHierarchy>(Method.Get, path, queryParams, undefined, {
+            prefix: ClientPrefix.V1,
         }).catch(e => {
             if (e.errcode === "M_UNRECOGNIZED") {
                 // fall back to the prefixed hierarchy API.
-                return this.http.authedRequest<IRoomHierarchy>(undefined, Method.Get, path, queryParams, undefined, {
+                return this.http.authedRequest<IRoomHierarchy>(Method.Get, path, queryParams, undefined, {
                     prefix: "/_matrix/client/unstable/org.matrix.msc2946",
                 });
             }
@@ -9179,7 +8837,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
             power_level_content_override: {
                 ...DEFAULT_TREE_POWER_LEVELS_TEMPLATE,
                 users: {
-                    [this.getUserId()]: 100,
+                    [this.getUserId()!]: 100,
                 },
             },
             creation_content: {
@@ -9234,12 +8892,15 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * Perform a single MSC3575 sliding sync request.
      * @param {MSC3575SlidingSyncRequest} req The request to make.
      * @param {string} proxyBaseUrl The base URL for the sliding sync proxy.
+     * @param {AbortSignal} abortSignal Optional signal to abort request mid-flight.
      * @returns {MSC3575SlidingSyncResponse} The sliding sync response, or a standard error.
      * @throws on non 2xx status codes with an object with a field "httpStatus":number.
      */
     public slidingSync(
-        req: MSC3575SlidingSyncRequest, proxyBaseUrl?: string,
-    ): IAbortablePromise<MSC3575SlidingSyncResponse> {
+        req: MSC3575SlidingSyncRequest,
+        proxyBaseUrl?: string,
+        abortSignal?: AbortSignal,
+    ): Promise<MSC3575SlidingSyncResponse> {
         const qps: Record<string, any> = {};
         if (req.pos) {
             qps.pos = req.pos;
@@ -9252,7 +8913,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         const clientTimeout = req.clientTimeout;
         delete req.clientTimeout;
         return this.http.authedRequest<MSC3575SlidingSyncResponse>(
-            undefined,
             Method.Post,
             "/sync",
             qps,
@@ -9261,6 +8921,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 prefix: "/_matrix/client/unstable/org.matrix.msc3575",
                 baseUrl: proxyBaseUrl,
                 localTimeoutMs: clientTimeout,
+                abortSignal,
             },
         );
     }
@@ -9280,8 +8941,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      */
     public async getRoomSummary(roomIdOrAlias: string, via?: string[]): Promise<IRoomSummary> {
         const path = utils.encodeUri("/rooms/$roomid/summary", { $roomid: roomIdOrAlias });
-        return this.http.authedRequest(undefined, Method.Get, path, { via }, undefined, {
-            qsStringifyOptions: { arrayFormat: 'repeat' },
+        return this.http.authedRequest(Method.Get, path, { via }, undefined, {
             prefix: "/_matrix/client/unstable/im.nheko.summary",
         });
     }
@@ -9314,7 +8974,7 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * Fetches the user_id of the configured access token.
      */
     public async whoami(): Promise<{ user_id: string }> { // eslint-disable-line camelcase
-        return this.http.authedRequest(undefined, Method.Get, "/account/whoami");
+        return this.http.authedRequest(Method.Get, "/account/whoami");
     }
 
     /**
@@ -9333,7 +8993,6 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         });
 
         return this.http.authedRequest(
-            undefined,
             Method.Get,
             path,
             {
diff --git a/src/crypto/EncryptionSetup.ts b/src/crypto/EncryptionSetup.ts
index d7c826d120a..d5d9877bdd8 100644
--- a/src/crypto/EncryptionSetup.ts
+++ b/src/crypto/EncryptionSetup.ts
@@ -18,7 +18,7 @@ import { logger } from "../logger";
 import { MatrixEvent } from "../models/event";
 import { createCryptoStoreCacheCallbacks, ICacheCallbacks } from "./CrossSigning";
 import { IndexedDBCryptoStore } from './store/indexeddb-crypto-store';
-import { Method, PREFIX_V3 } from "../http-api";
+import { Method, ClientPrefix } from "../http-api";
 import { Crypto, IBootstrapCrossSigningOpts } from "./index";
 import {
     ClientEvent,
@@ -241,19 +241,19 @@ export class EncryptionSetupOperation {
                 // Sign the backup with the cross signing key so the key backup can
                 // be trusted via cross-signing.
                 await baseApis.http.authedRequest(
-                    undefined, Method.Put, "/room_keys/version/" + this.keyBackupInfo.version,
+                    Method.Put, "/room_keys/version/" + this.keyBackupInfo.version,
                     undefined, {
                         algorithm: this.keyBackupInfo.algorithm,
                         auth_data: this.keyBackupInfo.auth_data,
                     },
-                    { prefix: PREFIX_V3 },
+                    { prefix: ClientPrefix.V3 },
                 );
             } else {
                 // add new key backup
                 await baseApis.http.authedRequest(
-                    undefined, Method.Post, "/room_keys/version",
+                    Method.Post, "/room_keys/version",
                     undefined, this.keyBackupInfo,
-                    { prefix: PREFIX_V3 },
+                    { prefix: ClientPrefix.V3 },
                 );
             }
         }
diff --git a/src/crypto/dehydration.ts b/src/crypto/dehydration.ts
index b775d76069f..b06561936b4 100644
--- a/src/crypto/dehydration.ts
+++ b/src/crypto/dehydration.ts
@@ -210,7 +210,6 @@ export class DehydrationManager {
             logger.log("Uploading account to server");
             // eslint-disable-next-line camelcase
             const dehydrateResult = await this.crypto.baseApis.http.authedRequest<{ device_id: string }>(
-                undefined,
                 Method.Put,
                 "/dehydrated_device",
                 undefined,
@@ -273,7 +272,6 @@ export class DehydrationManager {
 
             logger.log("Uploading keys to server");
             await this.crypto.baseApis.http.authedRequest(
-                undefined,
                 Method.Post,
                 "/keys/upload/" + encodeURI(deviceId),
                 undefined,
diff --git a/src/http-api.ts b/src/http-api.ts
deleted file mode 100644
index 1a7376b00a0..00000000000
--- a/src/http-api.ts
+++ /dev/null
@@ -1,1140 +0,0 @@
-/*
-Copyright 2015, 2016 OpenMarket Ltd
-Copyright 2019 - 2021 The Matrix.org Foundation C.I.C.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-/**
- * This is an internal module. See {@link MatrixHttpApi} for the public class.
- * @module http-api
- */
-
-import { parse as parseContentType, ParsedMediaType } from "content-type";
-
-import type { IncomingHttpHeaders, IncomingMessage } from "http";
-import type { Request as _Request, CoreOptions } from "request";
-// we use our own implementation of setTimeout, so that if we get suspended in
-// the middle of a /sync, we cancel the sync as soon as we awake, rather than
-// waiting for the delay to elapse.
-import * as callbacks from "./realtime-callbacks";
-import { IUploadOpts } from "./@types/requests";
-import { IAbortablePromise, IUsageLimit } from "./@types/partials";
-import { IDeferred, sleep } from "./utils";
-import { Callback } from "./client";
-import * as utils from "./utils";
-import { logger } from './logger';
-import { TypedEventEmitter } from "./models/typed-event-emitter";
-
-/*
-TODO:
-- CS: complete register function (doing stages)
-- Identity server: linkEmail, authEmail, bindEmail, lookup3pid
-*/
-
-/**
- * A constant representing the URI path for release 0 of the Client-Server HTTP API.
- */
-export const PREFIX_R0 = "/_matrix/client/r0";
-
-/**
- * A constant representing the URI path for the legacy release v1 of the Client-Server HTTP API.
- */
-export const PREFIX_V1 = "/_matrix/client/v1";
-
-/**
- * A constant representing the URI path for Client-Server API endpoints versioned at v3.
- */
-export const PREFIX_V3 = "/_matrix/client/v3";
-
-/**
- * A constant representing the URI path for as-yet unspecified Client-Server HTTP APIs.
- */
-export const PREFIX_UNSTABLE = "/_matrix/client/unstable";
-
-/**
- * URI path for v1 of the the identity API
- * @deprecated Use v2.
- */
-export const PREFIX_IDENTITY_V1 = "/_matrix/identity/api/v1";
-
-/**
- * URI path for the v2 identity API
- */
-export const PREFIX_IDENTITY_V2 = "/_matrix/identity/v2";
-
-/**
- * URI path for the media repo API
- */
-export const PREFIX_MEDIA_R0 = "/_matrix/media/r0";
-
-type RequestProps = "method"
-    | "withCredentials"
-    | "json"
-    | "headers"
-    | "qs"
-    | "body"
-    | "qsStringifyOptions"
-    | "useQuerystring"
-    | "timeout";
-
-export interface IHttpOpts {
-    baseUrl: string;
-    idBaseUrl?: string;
-    prefix: string;
-    onlyData: boolean;
-    accessToken?: string;
-    extraParams?: Record<string, string>;
-    localTimeoutMs?: number;
-    useAuthorizationHeader?: boolean;
-    request(opts: Pick<CoreOptions, RequestProps> & {
-        uri: string;
-        method: Method;
-        // eslint-disable-next-line camelcase
-        _matrix_opts: IHttpOpts;
-    }, callback: RequestCallback): IRequest;
-}
-
-interface IRequest extends _Request {
-    onprogress?(e: unknown): void;
-}
-
-interface IRequestOpts<T> {
-    prefix?: string;
-    baseUrl?: string;
-    localTimeoutMs?: number;
-    headers?: Record<string, string>;
-    json?: boolean; // defaults to true
-    qsStringifyOptions?: CoreOptions["qsStringifyOptions"];
-    bodyParser?(body: string): T;
-
-    // Set to true to prevent the request function from emitting
-    // a Session.logged_out event. This is intended for use on
-    // endpoints where M_UNKNOWN_TOKEN is a valid/notable error
-    // response, such as with token refreshes.
-    inhibitLogoutEmit?: boolean;
-}
-
-export interface IUpload {
-    loaded: number;
-    total: number;
-    promise: IAbortablePromise<unknown>;
-}
-
-interface IContentUri {
-    base: string;
-    path: string;
-    params: {
-        // eslint-disable-next-line camelcase
-        access_token: string;
-    };
-}
-
-type ResponseType<T, O extends IRequestOpts<T> | void = void> =
-    O extends { bodyParser: (body: string) => T } ? T :
-    O extends { json: false } ? string :
-    T;
-
-interface IUploadResponse {
-    // eslint-disable-next-line camelcase
-    content_uri: string;
-}
-
-// This type's defaults only work for the Browser
-// in the Browser we default rawResponse = false & onlyContentUri = true
-// in Node we default rawResponse = true & onlyContentUri = false
-export type UploadContentResponseType<O extends IUploadOpts> =
-    O extends undefined ? string :
-    O extends { rawResponse: true } ? string :
-    O extends { onlyContentUri: true } ? string :
-    O extends { rawResponse: false } ? IUploadResponse :
-    O extends { onlyContentUri: false } ? IUploadResponse :
-    string;
-
-export enum Method {
-    Get = "GET",
-    Put = "PUT",
-    Post = "POST",
-    Delete = "DELETE",
-}
-
-export type FileType = Document | XMLHttpRequestBodyInit;
-
-export enum HttpApiEvent {
-    SessionLoggedOut = "Session.logged_out",
-    NoConsent = "no_consent",
-}
-
-export type HttpApiEventHandlerMap = {
-    [HttpApiEvent.SessionLoggedOut]: (err: MatrixError) => void;
-    [HttpApiEvent.NoConsent]: (message: string, consentUri: string) => void;
-};
-
-/**
- * Construct a MatrixHttpApi.
- * @constructor
- * @param {EventEmitter} eventEmitter The event emitter to use for emitting events
- * @param {Object} opts The options to use for this HTTP API.
- * @param {string} opts.baseUrl Required. The base client-server URL e.g.
- * 'http://localhost:8008'.
- * @param {Function} opts.request Required. The function to call for HTTP
- * requests. This function must look like function(opts, callback){ ... }.
- * @param {string} opts.prefix Required. The matrix client prefix to use, e.g.
- * '/_matrix/client/r0'. See PREFIX_R0 and PREFIX_UNSTABLE for constants.
- *
- * @param {boolean} opts.onlyData True to return only the 'data' component of the
- * response (e.g. the parsed HTTP body). If false, requests will return an
- * object with the properties <tt>code</tt>, <tt>headers</tt> and <tt>data</tt>.
- *
- * @param {string=} opts.accessToken The access_token to send with requests. Can be
- * null to not send an access token.
- * @param {Object=} opts.extraParams Optional. Extra query parameters to send on
- * requests.
- * @param {Number=} opts.localTimeoutMs The default maximum amount of time to wait
- * before timing out the request. If not specified, there is no timeout.
- * @param {boolean} [opts.useAuthorizationHeader = false] Set to true to use
- * Authorization header instead of query param to send the access token to the server.
- */
-export class MatrixHttpApi {
-    private uploads: IUpload[] = [];
-
-    constructor(
-        private eventEmitter: TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>,
-        public readonly opts: IHttpOpts,
-    ) {
-        utils.checkObjectHasKeys(opts, ["baseUrl", "request", "prefix"]);
-        opts.onlyData = !!opts.onlyData;
-        opts.useAuthorizationHeader = !!opts.useAuthorizationHeader;
-    }
-
-    /**
-     * Sets the base URL for the identity server
-     * @param {string} url The new base url
-     */
-    public setIdBaseUrl(url: string): void {
-        this.opts.idBaseUrl = url;
-    }
-
-    /**
-     * Get the content repository url with query parameters.
-     * @return {Object} An object with a 'base', 'path' and 'params' for base URL,
-     *          path and query parameters respectively.
-     */
-    public getContentUri(): IContentUri {
-        return {
-            base: this.opts.baseUrl,
-            path: "/_matrix/media/r0/upload",
-            params: {
-                access_token: this.opts.accessToken,
-            },
-        };
-    }
-
-    /**
-     * Upload content to the homeserver
-     *
-     * @param {object} file The object to upload. On a browser, something that
-     *   can be sent to XMLHttpRequest.send (typically a File).  Under node.js,
-     *   a Buffer, String or ReadStream.
-     *
-     * @param {object} opts  options object
-     *
-     * @param {string=} opts.name   Name to give the file on the server. Defaults
-     *   to <tt>file.name</tt>.
-     *
-     * @param {boolean=} opts.includeFilename if false will not send the filename,
-     *   e.g for encrypted file uploads where filename leaks are undesirable.
-     *   Defaults to true.
-     *
-     * @param {string=} opts.type   Content-type for the upload. Defaults to
-     *   <tt>file.type</tt>, or <tt>applicaton/octet-stream</tt>.
-     *
-     * @param {boolean=} opts.rawResponse Return the raw body, rather than
-     *   parsing the JSON. Defaults to false (except on node.js, where it
-     *   defaults to true for backwards compatibility).
-     *
-     * @param {boolean=} opts.onlyContentUri Just return the content URI,
-     *   rather than the whole body. Defaults to false (except on browsers,
-     *   where it defaults to true for backwards compatibility). Ignored if
-     *   opts.rawResponse is true.
-     *
-     * @param {Function=} opts.callback Deprecated. Optional. The callback to
-     *    invoke on success/failure. See the promise return values for more
-     *    information.
-     *
-     * @param {Function=} opts.progressHandler Optional. Called when a chunk of
-     *    data has been uploaded, with an object containing the fields `loaded`
-     *    (number of bytes transferred) and `total` (total size, if known).
-     *
-     * @return {Promise} Resolves to response object, as
-     *    determined by this.opts.onlyData, opts.rawResponse, and
-     *    opts.onlyContentUri.  Rejects with an error (usually a MatrixError).
-     */
-    public uploadContent<O extends IUploadOpts>(
-        file: FileType,
-        opts?: O,
-    ): IAbortablePromise<UploadContentResponseType<O>> {
-        if (utils.isFunction(opts)) {
-            // opts used to be callback, backwards compatibility
-            opts = {
-                callback: opts as unknown as IUploadOpts["callback"],
-            } as O;
-        } else if (!opts) {
-            opts = {} as O;
-        }
-
-        // default opts.includeFilename to true (ignoring falsey values)
-        const includeFilename = opts.includeFilename !== false;
-
-        // if the file doesn't have a mime type, use a default since
-        // the HS errors if we don't supply one.
-        const contentType = opts.type || (file as File).type || 'application/octet-stream';
-        const fileName = opts.name || (file as File).name;
-
-        // We used to recommend setting file.stream to the thing to upload on
-        // Node.js. As of 2019-06-11, this is still in widespread use in various
-        // clients, so we should preserve this for simple objects used in
-        // Node.js. File API objects (via either the File or Blob interfaces) in
-        // the browser now define a `stream` method, which leads to trouble
-        // here, so we also check the type of `stream`.
-        let body = file;
-        const bodyStream = (body as File | Blob).stream; // this type is wrong but for legacy reasons is good enough
-        if (bodyStream && typeof bodyStream !== "function") {
-            logger.warn(
-                "Using `file.stream` as the content to upload. Future " +
-                "versions of the js-sdk will change this to expect `file` to " +
-                "be the content directly.",
-            );
-            body = bodyStream;
-        }
-
-        // backwards-compatibility hacks where we used to do different things
-        // between browser and node.
-        let rawResponse = opts.rawResponse;
-        if (rawResponse === undefined) {
-            if (global.XMLHttpRequest) {
-                rawResponse = false;
-            } else {
-                logger.warn(
-                    "Returning the raw JSON from uploadContent(). Future " +
-                    "versions of the js-sdk will change this default, to " +
-                    "return the parsed object. Set opts.rawResponse=false " +
-                    "to change this behaviour now.",
-                );
-                rawResponse = true;
-            }
-        }
-
-        let onlyContentUri = opts.onlyContentUri;
-        if (!rawResponse && onlyContentUri === undefined) {
-            if (global.XMLHttpRequest) {
-                logger.warn(
-                    "Returning only the content-uri from uploadContent(). " +
-                    "Future versions of the js-sdk will change this " +
-                    "default, to return the whole response object. Set " +
-                    "opts.onlyContentUri=false to change this behaviour now.",
-                );
-                onlyContentUri = true;
-            } else {
-                onlyContentUri = false;
-            }
-        }
-
-        // browser-request doesn't support File objects because it deep-copies
-        // the options using JSON.parse(JSON.stringify(options)). Instead of
-        // loading the whole file into memory as a string and letting
-        // browser-request base64 encode and then decode it again, we just
-        // use XMLHttpRequest directly.
-        // (browser-request doesn't support progress either, which is also kind
-        // of important here)
-
-        const upload = { loaded: 0, total: 0 } as IUpload;
-        let promise: IAbortablePromise<UploadContentResponseType<O>>;
-
-        // XMLHttpRequest doesn't parse JSON for us. request normally does, but
-        // we're setting opts.json=false so that it doesn't JSON-encode the
-        // request, which also means it doesn't JSON-decode the response. Either
-        // way, we have to JSON-parse the response ourselves.
-        let bodyParser: ((body: string) => any) | undefined;
-        if (!rawResponse) {
-            bodyParser = function(rawBody: string) {
-                let body = JSON.parse(rawBody);
-                if (onlyContentUri) {
-                    body = body.content_uri;
-                    if (body === undefined) {
-                        throw Error('Bad response');
-                    }
-                }
-                return body;
-            };
-        }
-
-        if (global.XMLHttpRequest) {
-            const defer = utils.defer<UploadContentResponseType<O>>();
-            const xhr = new global.XMLHttpRequest();
-            const cb = requestCallback(defer, opts.callback, this.opts.onlyData);
-
-            const timeoutFn = function() {
-                xhr.abort();
-                cb(new Error('Timeout'));
-            };
-
-            // set an initial timeout of 30s; we'll advance it each time we get a progress notification
-            let timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);
-
-            xhr.onreadystatechange = function() {
-                let resp: string;
-                switch (xhr.readyState) {
-                    case global.XMLHttpRequest.DONE:
-                        callbacks.clearTimeout(timeoutTimer);
-                        try {
-                            if (xhr.status === 0) {
-                                throw new AbortError();
-                            }
-                            if (!xhr.responseText) {
-                                throw new Error('No response body.');
-                            }
-                            resp = xhr.responseText;
-                            if (bodyParser) {
-                                resp = bodyParser(resp);
-                            }
-                        } catch (err) {
-                            err.httpStatus = xhr.status;
-                            cb(err);
-                            return;
-                        }
-                        cb(undefined, xhr, resp);
-                        break;
-                }
-            };
-            xhr.upload.addEventListener("progress", function(ev) {
-                callbacks.clearTimeout(timeoutTimer);
-                upload.loaded = ev.loaded;
-                upload.total = ev.total;
-                timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);
-                if (opts.progressHandler) {
-                    opts.progressHandler({
-                        loaded: ev.loaded,
-                        total: ev.total,
-                    });
-                }
-            });
-            let url = this.opts.baseUrl + "/_matrix/media/r0/upload";
-
-            const queryArgs = [];
-
-            if (includeFilename && fileName) {
-                queryArgs.push("filename=" + encodeURIComponent(fileName));
-            }
-
-            if (!this.opts.useAuthorizationHeader) {
-                queryArgs.push("access_token=" + encodeURIComponent(this.opts.accessToken));
-            }
-
-            if (queryArgs.length > 0) {
-                url += "?" + queryArgs.join("&");
-            }
-
-            xhr.open("POST", url);
-            if (this.opts.useAuthorizationHeader) {
-                xhr.setRequestHeader("Authorization", "Bearer " + this.opts.accessToken);
-            }
-            xhr.setRequestHeader("Content-Type", contentType);
-            xhr.send(body);
-            promise = defer.promise as IAbortablePromise<UploadContentResponseType<O>>;
-
-            // dirty hack (as per doRequest) to allow the upload to be cancelled.
-            promise.abort = xhr.abort.bind(xhr);
-        } else {
-            const queryParams: Record<string, string> = {};
-
-            if (includeFilename && fileName) {
-                queryParams.filename = fileName;
-            }
-
-            const headers: Record<string, string> = { "Content-Type": contentType };
-
-            // authedRequest uses `request` which is no longer maintained.
-            // `request` has a bug where if the body is zero bytes then you get an error: `Argument error, options.body`.
-            // See https://github.com/request/request/issues/920
-            // if body looks like a byte array and empty then set the Content-Length explicitly as a workaround:
-            if ((body as unknown as ArrayLike<number>).length === 0) {
-                headers["Content-Length"] = "0";
-            }
-
-            promise = this.authedRequest<UploadContentResponseType<O>>(
-                opts.callback, Method.Post, "/upload", queryParams, body, {
-                    prefix: "/_matrix/media/r0",
-                    headers,
-                    json: false,
-                    bodyParser,
-                },
-            );
-        }
-
-        // remove the upload from the list on completion
-        upload.promise = promise.finally(() => {
-            for (let i = 0; i < this.uploads.length; ++i) {
-                if (this.uploads[i] === upload) {
-                    this.uploads.splice(i, 1);
-                    return;
-                }
-            }
-        }) as IAbortablePromise<UploadContentResponseType<O>>;
-
-        // copy our dirty abort() method to the new promise
-        upload.promise.abort = promise.abort;
-        this.uploads.push(upload);
-
-        return upload.promise as IAbortablePromise<UploadContentResponseType<O>>;
-    }
-
-    public cancelUpload(promise: IAbortablePromise<unknown>): boolean {
-        if (promise.abort) {
-            promise.abort();
-            return true;
-        }
-        return false;
-    }
-
-    public getCurrentUploads(): IUpload[] {
-        return this.uploads;
-    }
-
-    public idServerRequest<T>(
-        callback: Callback<T>,
-        method: Method,
-        path: string,
-        params: Record<string, string | string[]>,
-        prefix: string,
-        accessToken: string,
-    ): Promise<T> {
-        if (!this.opts.idBaseUrl) {
-            throw new Error("No identity server base URL set");
-        }
-
-        const fullUri = this.opts.idBaseUrl + prefix + path;
-
-        if (callback !== undefined && !utils.isFunction(callback)) {
-            throw Error(
-                "Expected callback to be a function but got " + typeof callback,
-            );
-        }
-
-        const opts = {
-            uri: fullUri,
-            method,
-            withCredentials: false,
-            json: true, // we want a JSON response if we can
-            _matrix_opts: this.opts,
-            headers: {},
-        } as Parameters<IHttpOpts["request"]>[0];
-
-        if (method === Method.Get) {
-            opts.qs = params;
-        } else if (typeof params === "object") {
-            opts.json = params;
-        }
-
-        if (accessToken) {
-            opts.headers['Authorization'] = `Bearer ${accessToken}`;
-        }
-
-        const defer = utils.defer<T>();
-        this.opts.request(opts, requestCallback(defer, callback, this.opts.onlyData));
-        return defer.promise;
-    }
-
-    /**
-     * Perform an authorised request to the homeserver.
-     * @param {Function} callback Optional. The callback to invoke on
-     * success/failure. See the promise return values for more information.
-     * @param {string} method The HTTP method e.g. "GET".
-     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
-     * "/createRoom".
-     *
-     * @param {Object=} queryParams A dict of query params (these will NOT be
-     * urlencoded). If unspecified, there will be no query params.
-     *
-     * @param {Object} [data] The HTTP JSON body.
-     *
-     * @param {Object|Number=} opts additional options. If a number is specified,
-     * this is treated as `opts.localTimeoutMs`.
-     *
-     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
-     * timing out the request. If not specified, there is no timeout.
-     *
-     * @param {string=} opts.prefix The full prefix to use e.g.
-     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
-     *
-     * @param {string=} opts.baseUrl The alternative base url to use.
-     * If not specified, uses this.opts.baseUrl
-     *
-     * @param {Object=} opts.headers map of additional request headers
-     *
-     * @return {Promise} Resolves to <code>{data: {Object},
-     * headers: {Object}, code: {Number}}</code>.
-     * If <code>onlyData</code> is set, this will resolve to the <code>data</code>
-     * object only.
-     * @return {module:http-api.MatrixError} Rejects with an error if a problem
-     * occurred. This includes network problems and Matrix-specific error JSON.
-     */
-    public authedRequest<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
-        callback: Callback<T> | undefined,
-        method: Method,
-        path: string,
-        queryParams?: Record<string, string | string[] | undefined>,
-        data?: CoreOptions["body"],
-        opts?: O | number, // number is legacy
-    ): IAbortablePromise<ResponseType<T, O>> {
-        if (!queryParams) queryParams = {};
-        let requestOpts = (opts || {}) as O;
-
-        if (this.opts.useAuthorizationHeader) {
-            if (isFinite(opts as number)) {
-                // opts used to be localTimeoutMs
-                requestOpts = {
-                    localTimeoutMs: opts as number,
-                } as O;
-            }
-
-            if (!requestOpts.headers) {
-                requestOpts.headers = {};
-            }
-            if (!requestOpts.headers.Authorization) {
-                requestOpts.headers.Authorization = "Bearer " + this.opts.accessToken;
-            }
-            if (queryParams.access_token) {
-                delete queryParams.access_token;
-            }
-        } else if (!queryParams.access_token) {
-            queryParams.access_token = this.opts.accessToken;
-        }
-
-        const requestPromise = this.request<T, O>(callback, method, path, queryParams, data, requestOpts);
-
-        requestPromise.catch((err: MatrixError) => {
-            if (err.errcode == 'M_UNKNOWN_TOKEN' && !requestOpts?.inhibitLogoutEmit) {
-                this.eventEmitter.emit(HttpApiEvent.SessionLoggedOut, err);
-            } else if (err.errcode == 'M_CONSENT_NOT_GIVEN') {
-                this.eventEmitter.emit(HttpApiEvent.NoConsent, err.message, err.data.consent_uri);
-            }
-        });
-
-        // return the original promise, otherwise tests break due to it having to
-        // go around the event loop one more time to process the result of the request
-        return requestPromise;
-    }
-
-    /**
-     * Perform a request to the homeserver without any credentials.
-     * @param {Function} callback Optional. The callback to invoke on
-     * success/failure. See the promise return values for more information.
-     * @param {string} method The HTTP method e.g. "GET".
-     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
-     * "/createRoom".
-     *
-     * @param {Object=} queryParams A dict of query params (these will NOT be
-     * urlencoded). If unspecified, there will be no query params.
-     *
-     * @param {Object} [data] The HTTP JSON body.
-     *
-     * @param {Object=} opts additional options
-     *
-     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
-     * timing out the request. If not specified, there is no timeout.
-     *
-     * @param {string=} opts.prefix The full prefix to use e.g.
-     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
-     *
-     * @param {Object=} opts.headers map of additional request headers
-     *
-     * @return {Promise} Resolves to <code>{data: {Object},
-     * headers: {Object}, code: {Number}}</code>.
-     * If <code>onlyData</code> is set, this will resolve to the <code>data</code>
-     * object only.
-     * @return {module:http-api.MatrixError} Rejects with an error if a problem
-     * occurred. This includes network problems and Matrix-specific error JSON.
-     */
-    public request<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
-        callback: Callback<T> | undefined,
-        method: Method,
-        path: string,
-        queryParams?: CoreOptions["qs"],
-        data?: CoreOptions["body"],
-        opts?: O,
-    ): IAbortablePromise<ResponseType<T, O>> {
-        const prefix = opts?.prefix ?? this.opts.prefix;
-        const baseUrl = opts?.baseUrl ?? this.opts.baseUrl;
-        const fullUri = baseUrl + prefix + path;
-
-        return this.requestOtherUrl<T, O>(callback, method, fullUri, queryParams, data, opts);
-    }
-
-    /**
-     * Perform a request to an arbitrary URL.
-     * @param {Function} callback Optional. The callback to invoke on
-     * success/failure. See the promise return values for more information.
-     * @param {string} method The HTTP method e.g. "GET".
-     * @param {string} uri The HTTP URI
-     *
-     * @param {Object=} queryParams A dict of query params (these will NOT be
-     * urlencoded). If unspecified, there will be no query params.
-     *
-     * @param {Object} [data] The HTTP JSON body.
-     *
-     * @param {Object=} opts additional options
-     *
-     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
-     * timing out the request. If not specified, there is no timeout.
-     *
-     * @param {string=} opts.prefix The full prefix to use e.g.
-     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
-     *
-     * @param {Object=} opts.headers map of additional request headers
-     *
-     * @return {Promise} Resolves to <code>{data: {Object},
-     * headers: {Object}, code: {Number}}</code>.
-     * If <code>onlyData</code> is set, this will resolve to the <code>data</code>
-     * object only.
-     * @return {module:http-api.MatrixError} Rejects with an error if a problem
-     * occurred. This includes network problems and Matrix-specific error JSON.
-     */
-    public requestOtherUrl<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
-        callback: Callback<T> | undefined,
-        method: Method,
-        uri: string,
-        queryParams?: CoreOptions["qs"],
-        data?: CoreOptions["body"],
-        opts?: O | number, // number is legacy
-    ): IAbortablePromise<ResponseType<T, O>> {
-        let requestOpts = (opts || {}) as O;
-        if (isFinite(opts as number)) {
-            // opts used to be localTimeoutMs
-            requestOpts = {
-                localTimeoutMs: opts as number,
-            } as O;
-        }
-
-        return this.doRequest<T, O>(callback, method, uri, queryParams, data, requestOpts);
-    }
-
-    /**
-     * Form and return a homeserver request URL based on the given path
-     * params and prefix.
-     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
-     * "/createRoom".
-     * @param {Object} queryParams A dict of query params (these will NOT be
-     * urlencoded).
-     * @param {string} prefix The full prefix to use e.g.
-     * "/_matrix/client/v2_alpha".
-     * @return {string} URL
-     */
-    public getUrl(path: string, queryParams: CoreOptions["qs"], prefix: string): string {
-        let queryString = "";
-        if (queryParams) {
-            queryString = "?" + utils.encodeParams(queryParams);
-        }
-        return this.opts.baseUrl + prefix + path + queryString;
-    }
-
-    /**
-     * @private
-     *
-     * @param {function} callback
-     * @param {string} method
-     * @param {string} uri
-     * @param {object} queryParams
-     * @param {object|string} data
-     * @param {object=} opts
-     *
-     * @param {boolean} [opts.json =true] Json-encode data before sending, and
-     *   decode response on receipt. (We will still json-decode error
-     *   responses, even if this is false.)
-     *
-     * @param {object=} opts.headers  extra request headers
-     *
-     * @param {number=} opts.localTimeoutMs client-side timeout for the
-     *    request. Default timeout if falsy.
-     *
-     * @param {function=} opts.bodyParser function to parse the body of the
-     *    response before passing it to the promise and callback.
-     *
-     * @return {Promise} a promise which resolves to either the
-     * response object (if this.opts.onlyData is truthy), or the parsed
-     * body. Rejects
-     *
-     * Generic T is the callback/promise resolve type
-     * Generic O should be inferred
-     */
-    private doRequest<T, O extends IRequestOpts<T> = IRequestOpts<T>>(
-        callback: Callback<T> | undefined,
-        method: Method,
-        uri: string,
-        queryParams?: Record<string, string>,
-        data?: CoreOptions["body"],
-        opts?: O,
-    ): IAbortablePromise<ResponseType<T, O>> {
-        if (callback !== undefined && !utils.isFunction(callback)) {
-            throw Error("Expected callback to be a function but got " + typeof callback);
-        }
-
-        if (this.opts.extraParams) {
-            queryParams = {
-                ...(queryParams || {}),
-                ...this.opts.extraParams,
-            };
-        }
-
-        const headers = Object.assign({}, opts.headers || {});
-        if (!opts) opts = {} as O;
-        const json = opts.json ?? true;
-        let bodyParser = opts.bodyParser;
-
-        // we handle the json encoding/decoding here, because request and
-        // browser-request make a mess of it. Specifically, they attempt to
-        // json-decode plain-text error responses, which in turn means that the
-        // actual error gets swallowed by a SyntaxError.
-
-        if (json) {
-            if (data) {
-                data = JSON.stringify(data);
-                headers['content-type'] = 'application/json';
-            }
-
-            if (!headers['accept']) {
-                headers['accept'] = 'application/json';
-            }
-
-            if (bodyParser === undefined) {
-                bodyParser = function(rawBody: string) {
-                    return JSON.parse(rawBody);
-                };
-            }
-        }
-
-        const defer = utils.defer<T>();
-
-        let timeoutId: number;
-        let timedOut = false;
-        let req: IRequest;
-        const localTimeoutMs = opts.localTimeoutMs || this.opts.localTimeoutMs;
-
-        const resetTimeout = () => {
-            if (localTimeoutMs) {
-                if (timeoutId) {
-                    callbacks.clearTimeout(timeoutId);
-                }
-                timeoutId = callbacks.setTimeout(function() {
-                    timedOut = true;
-                    req?.abort?.();
-                    defer.reject(new MatrixError({
-                        error: "Locally timed out waiting for a response",
-                        errcode: "ORG.MATRIX.JSSDK_TIMEOUT",
-                        timeout: localTimeoutMs,
-                    }));
-                }, localTimeoutMs);
-            }
-        };
-        resetTimeout();
-
-        const reqPromise = defer.promise as IAbortablePromise<ResponseType<T, O>>;
-
-        try {
-            req = this.opts.request(
-                {
-                    uri: uri,
-                    method: method,
-                    withCredentials: false,
-                    qs: queryParams,
-                    qsStringifyOptions: opts.qsStringifyOptions,
-                    useQuerystring: true,
-                    body: data,
-                    json: false,
-                    timeout: localTimeoutMs,
-                    headers: headers || {},
-                    _matrix_opts: this.opts,
-                },
-                (err, response, body) => {
-                    if (localTimeoutMs) {
-                        callbacks.clearTimeout(timeoutId);
-                        if (timedOut) {
-                            return; // already rejected promise
-                        }
-                    }
-
-                    const handlerFn = requestCallback(defer, callback, this.opts.onlyData, bodyParser);
-                    handlerFn(err, response, body);
-                },
-            );
-            if (req) {
-                // This will only work in a browser, where opts.request is the
-                // `browser-request` import. Currently, `request` does not support progress
-                // updates - see https://github.com/request/request/pull/2346.
-                // `browser-request` returns an XHRHttpRequest which exposes `onprogress`
-                if ('onprogress' in req) {
-                    req.onprogress = (e) => {
-                        // Prevent the timeout from rejecting the deferred promise if progress is
-                        // seen with the request
-                        resetTimeout();
-                    };
-                }
-
-                // FIXME: This is EVIL, but I can't think of a better way to expose
-                // abort() operations on underlying HTTP requests :(
-                if (req.abort) {
-                    reqPromise.abort = req.abort.bind(req);
-                }
-            }
-        } catch (ex) {
-            defer.reject(ex);
-            if (callback) {
-                callback(ex);
-            }
-        }
-        return reqPromise;
-    }
-}
-
-type RequestCallback = (err?: Error, response?: XMLHttpRequest | IncomingMessage, body?: string) => void;
-
-// if using onlyData=false then wrap your expected data type in this generic
-export interface IResponse<T> {
-    code: number;
-    data: T;
-    headers?: IncomingHttpHeaders;
-}
-
-function getStatusCode(response: XMLHttpRequest | IncomingMessage): number {
-    return (response as XMLHttpRequest).status || (response as IncomingMessage).statusCode;
-}
-
-/*
- * Returns a callback that can be invoked by an HTTP request on completion,
- * that will either resolve or reject the given defer as well as invoke the
- * given userDefinedCallback (if any).
- *
- * HTTP errors are transformed into javascript errors and the deferred is rejected.
- *
- * If bodyParser is given, it is used to transform the body of the successful
- * responses before passing to the defer/callback.
- *
- * If onlyData is true, the defer/callback is invoked with the body of the
- * response, otherwise the result object (with `code` and `data` fields)
- *
- */
-function requestCallback<T>(
-    defer: IDeferred<T>,
-    userDefinedCallback?: Callback<T>,
-    onlyData = false,
-    bodyParser?: (body: string) => T,
-): RequestCallback {
-    return function(err: Error, response: XMLHttpRequest | IncomingMessage, body: string): void {
-        if (err) {
-            // the unit tests use matrix-mock-request, which throw the string "aborted" when aborting a request.
-            // See https://github.com/matrix-org/matrix-mock-request/blob/3276d0263a561b5b8326b47bae720578a2c7473a/src/index.js#L48
-            const aborted = err.name === "AbortError" || (err as any as string) === "aborted";
-            if (!aborted && !(err instanceof MatrixError)) {
-                // browser-request just throws normal Error objects,
-                // not `TypeError`s like fetch does. So just assume any
-                // error is due to the connection.
-                err = new ConnectionError("request failed", err);
-            }
-        }
-
-        let data: T | string = body;
-
-        if (!err) {
-            try {
-                if (getStatusCode(response) >= 400) {
-                    err = parseErrorResponse(response, body);
-                } else if (bodyParser) {
-                    data = bodyParser(body);
-                }
-            } catch (e) {
-                err = new Error(`Error parsing server response: ${e}`);
-            }
-        }
-
-        if (err) {
-            defer.reject(err);
-            userDefinedCallback?.(err);
-        } else if (onlyData) {
-            defer.resolve(data as T);
-            userDefinedCallback?.(null, data as T);
-        } else {
-            const res: IResponse<T> = {
-                code: getStatusCode(response),
-
-                // XXX: why do we bother with this? it doesn't work for
-                // XMLHttpRequest, so clearly we don't use it.
-                headers: (response as IncomingMessage).headers,
-                data: data as T,
-            };
-            // XXX: the variations in caller-expected types here are horrible,
-            // typescript doesn't do conditional types based on runtime values
-            defer.resolve(res as any as T);
-            userDefinedCallback?.(null, res as any as T);
-        }
-    };
-}
-
-/**
- * Attempt to turn an HTTP error response into a Javascript Error.
- *
- * If it is a JSON response, we will parse it into a MatrixError. Otherwise
- * we return a generic Error.
- *
- * @param {XMLHttpRequest|http.IncomingMessage} response response object
- * @param {String} body raw body of the response
- * @returns {Error}
- */
-function parseErrorResponse(response: XMLHttpRequest | IncomingMessage, body?: string) {
-    const httpStatus = getStatusCode(response);
-    const contentType = getResponseContentType(response);
-
-    let err;
-    if (contentType) {
-        if (contentType.type === 'application/json') {
-            const jsonBody = typeof(body) === 'object' ? body : JSON.parse(body);
-            err = new MatrixError(jsonBody);
-        } else if (contentType.type === 'text/plain') {
-            err = new Error(`Server returned ${httpStatus} error: ${body}`);
-        }
-    }
-
-    if (!err) {
-        err = new Error(`Server returned ${httpStatus} error`);
-    }
-    err.httpStatus = httpStatus;
-    return err;
-}
-
-/**
- * extract the Content-Type header from the response object, and
- * parse it to a `{type, parameters}` object.
- *
- * returns null if no content-type header could be found.
- *
- * @param {XMLHttpRequest|http.IncomingMessage} response response object
- * @returns {{type: String, parameters: Object}?} parsed content-type header, or null if not found
- */
-function getResponseContentType(response: XMLHttpRequest | IncomingMessage): ParsedMediaType {
-    let contentType;
-    if ((response as XMLHttpRequest).getResponseHeader) {
-        // XMLHttpRequest provides getResponseHeader
-        contentType = (response as XMLHttpRequest).getResponseHeader("Content-Type");
-    } else if ((response as IncomingMessage).headers) {
-        // request provides http.IncomingMessage which has a message.headers map
-        contentType = (response as IncomingMessage).headers['content-type'] || null;
-    }
-
-    if (!contentType) {
-        return null;
-    }
-
-    try {
-        return parseContentType(contentType);
-    } catch (e) {
-        throw new Error(`Error parsing Content-Type '${contentType}': ${e}`);
-    }
-}
-
-interface IErrorJson extends Partial<IUsageLimit> {
-    [key: string]: any; // extensible
-    errcode?: string;
-    error?: string;
-}
-
-/**
- * Construct a Matrix error. This is a JavaScript Error with additional
- * information specific to the standard Matrix error response.
- * @constructor
- * @param {Object} errorJson The Matrix error JSON returned from the homeserver.
- * @prop {string} errcode The Matrix 'errcode' value, e.g. "M_FORBIDDEN".
- * @prop {string} name Same as MatrixError.errcode but with a default unknown string.
- * @prop {string} message The Matrix 'error' value, e.g. "Missing token."
- * @prop {Object} data The raw Matrix error JSON used to construct this object.
- * @prop {number} httpStatus The numeric HTTP status code given
- */
-export class MatrixError extends Error {
-    public readonly errcode: string;
-    public readonly data: IErrorJson;
-    public httpStatus?: number; // set by http-api
-
-    constructor(errorJson: IErrorJson = {}) {
-        super(`MatrixError: ${errorJson.errcode}`);
-        this.errcode = errorJson.errcode;
-        this.name = errorJson.errcode || "Unknown error code";
-        this.message = errorJson.error || "Unknown message";
-        this.data = errorJson;
-    }
-}
-
-/**
- * Construct a ConnectionError. This is a JavaScript Error indicating
- * that a request failed because of some error with the connection, either
- * CORS was not correctly configured on the server, the server didn't response,
- * the request timed out, or the internet connection on the client side went down.
- * @constructor
- */
-export class ConnectionError extends Error {
-    constructor(message: string, cause: Error = undefined) {
-        super(message + (cause ? `: ${cause.message}` : ""));
-    }
-
-    get name() {
-        return "ConnectionError";
-    }
-}
-
-export class AbortError extends Error {
-    constructor() {
-        super("Operation aborted");
-    }
-
-    get name() {
-        return "AbortError";
-    }
-}
-
-/**
- * Retries a network operation run in a callback.
- * @param  {number}   maxAttempts maximum attempts to try
- * @param  {Function} callback    callback that returns a promise of the network operation. If rejected with ConnectionError, it will be retried by calling the callback again.
- * @return {any} the result of the network operation
- * @throws {ConnectionError} If after maxAttempts the callback still throws ConnectionError
- */
-export async function retryNetworkOperation<T>(maxAttempts: number, callback: () => Promise<T>): Promise<T> {
-    let attempts = 0;
-    let lastConnectionError = null;
-    while (attempts < maxAttempts) {
-        try {
-            if (attempts > 0) {
-                const timeout = 1000 * Math.pow(2, attempts);
-                logger.log(`network operation failed ${attempts} times,` +
-                    ` retrying in ${timeout}ms...`);
-                await sleep(timeout);
-            }
-            return callback();
-        } catch (err) {
-            if (err instanceof ConnectionError) {
-                attempts += 1;
-                lastConnectionError = err;
-            } else {
-                throw err;
-            }
-        }
-    }
-    throw lastConnectionError;
-}
diff --git a/src/http-api/errors.ts b/src/http-api/errors.ts
new file mode 100644
index 00000000000..d44b23e7a2e
--- /dev/null
+++ b/src/http-api/errors.ts
@@ -0,0 +1,64 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { IUsageLimit } from "../@types/partials";
+
+interface IErrorJson extends Partial<IUsageLimit> {
+    [key: string]: any; // extensible
+    errcode?: string;
+    error?: string;
+}
+
+/**
+ * Construct a Matrix error. This is a JavaScript Error with additional
+ * information specific to the standard Matrix error response.
+ * @constructor
+ * @param {Object} errorJson The Matrix error JSON returned from the homeserver.
+ * @prop {string} errcode The Matrix 'errcode' value, e.g. "M_FORBIDDEN".
+ * @prop {string} name Same as MatrixError.errcode but with a default unknown string.
+ * @prop {string} message The Matrix 'error' value, e.g. "Missing token."
+ * @prop {Object} data The raw Matrix error JSON used to construct this object.
+ * @prop {number} httpStatus The numeric HTTP status code given
+ */
+export class MatrixError extends Error {
+    public readonly errcode?: string;
+    public readonly data: IErrorJson;
+
+    constructor(errorJson: IErrorJson = {}, public httpStatus?: number) {
+        super(`MatrixError: ${errorJson.errcode}`);
+        this.errcode = errorJson.errcode;
+        this.name = errorJson.errcode || "Unknown error code";
+        this.message = errorJson.error || "Unknown message";
+        this.data = errorJson;
+    }
+}
+
+/**
+ * Construct a ConnectionError. This is a JavaScript Error indicating
+ * that a request failed because of some error with the connection, either
+ * CORS was not correctly configured on the server, the server didn't response,
+ * the request timed out, or the internet connection on the client side went down.
+ * @constructor
+ */
+export class ConnectionError extends Error {
+    constructor(message: string, cause?: Error) {
+        super(message + (cause ? `: ${cause.message}` : ""));
+    }
+
+    get name() {
+        return "ConnectionError";
+    }
+}
diff --git a/src/http-api/fetch.ts b/src/http-api/fetch.ts
new file mode 100644
index 00000000000..4fecaaecf8d
--- /dev/null
+++ b/src/http-api/fetch.ts
@@ -0,0 +1,327 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+/**
+ * This is an internal module. See {@link MatrixHttpApi} for the public class.
+ * @module http-api
+ */
+
+import * as utils from "../utils";
+import { TypedEventEmitter } from "../models/typed-event-emitter";
+import { Method } from "./method";
+import { ConnectionError, MatrixError } from "./errors";
+import { HttpApiEvent, HttpApiEventHandlerMap, IHttpOpts, IRequestOpts } from "./interface";
+import { anySignal, parseErrorResponse, timeoutSignal } from "./utils";
+import { QueryDict } from "../utils";
+
+type Body = Record<string, any> | BodyInit;
+
+interface TypedResponse<T> extends Response {
+    json(): Promise<T>;
+}
+
+export type ResponseType<T, O extends IHttpOpts> =
+    O extends undefined ? T :
+        O extends { onlyData: true } ? T :
+            TypedResponse<T>;
+
+export class FetchHttpApi<O extends IHttpOpts> {
+    private abortController = new AbortController();
+
+    constructor(
+        private eventEmitter: TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>,
+        public readonly opts: O,
+    ) {
+        utils.checkObjectHasKeys(opts, ["baseUrl", "prefix"]);
+        opts.onlyData = !!opts.onlyData;
+        opts.useAuthorizationHeader = opts.useAuthorizationHeader ?? true;
+    }
+
+    public abort(): void {
+        this.abortController.abort();
+        this.abortController = new AbortController();
+    }
+
+    public fetch(resource: URL | string, options?: RequestInit): ReturnType<typeof global.fetch> {
+        if (this.opts.fetchFn) {
+            return this.opts.fetchFn(resource, options);
+        }
+        return global.fetch(resource, options);
+    }
+
+    /**
+     * Sets the base URL for the identity server
+     * @param {string} url The new base url
+     */
+    public setIdBaseUrl(url: string): void {
+        this.opts.idBaseUrl = url;
+    }
+
+    public idServerRequest<T extends {}>(
+        method: Method,
+        path: string,
+        params: Record<string, string | string[]>,
+        prefix: string,
+        accessToken?: string,
+    ): Promise<ResponseType<T, O>> {
+        if (!this.opts.idBaseUrl) {
+            throw new Error("No identity server base URL set");
+        }
+
+        let queryParams: QueryDict | undefined = undefined;
+        let body: Record<string, string | string[]> | undefined = undefined;
+        if (method === Method.Get) {
+            queryParams = params;
+        } else {
+            body = params;
+        }
+
+        const fullUri = this.getUrl(path, queryParams, prefix, this.opts.idBaseUrl);
+
+        const opts: IRequestOpts = {
+            json: true,
+            headers: {},
+        };
+        if (accessToken) {
+            opts.headers.Authorization = `Bearer ${accessToken}`;
+        }
+
+        return this.requestOtherUrl(method, fullUri, body, opts);
+    }
+
+    /**
+     * Perform an authorised request to the homeserver.
+     * @param {string} method The HTTP method e.g. "GET".
+     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
+     * "/createRoom".
+     *
+     * @param {Object=} queryParams A dict of query params (these will NOT be
+     * urlencoded). If unspecified, there will be no query params.
+     *
+     * @param {Object} [body] The HTTP JSON body.
+     *
+     * @param {Object|Number=} opts additional options. If a number is specified,
+     * this is treated as `opts.localTimeoutMs`.
+     *
+     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
+     * timing out the request. If not specified, there is no timeout.
+     *
+     * @param {string=} opts.prefix The full prefix to use e.g.
+     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
+     *
+     * @param {string=} opts.baseUrl The alternative base url to use.
+     * If not specified, uses this.opts.baseUrl
+     *
+     * @param {Object=} opts.headers map of additional request headers
+     *
+     * @return {Promise} Resolves to <code>{data: {Object},
+     * headers: {Object}, code: {Number}}</code>.
+     * If <code>onlyData</code> is set, this will resolve to the <code>data</code>
+     * object only.
+     * @return {module:http-api.MatrixError} Rejects with an error if a problem
+     * occurred. This includes network problems and Matrix-specific error JSON.
+     */
+    public authedRequest<T>(
+        method: Method,
+        path: string,
+        queryParams?: QueryDict,
+        body?: Body,
+        opts: IRequestOpts = {},
+    ): Promise<ResponseType<T, O>> {
+        if (!queryParams) queryParams = {};
+
+        if (this.opts.useAuthorizationHeader) {
+            if (!opts.headers) {
+                opts.headers = {};
+            }
+            if (!opts.headers.Authorization) {
+                opts.headers.Authorization = "Bearer " + this.opts.accessToken;
+            }
+            if (queryParams.access_token) {
+                delete queryParams.access_token;
+            }
+        } else if (!queryParams.access_token) {
+            queryParams.access_token = this.opts.accessToken;
+        }
+
+        const requestPromise = this.request<T>(method, path, queryParams, body, opts);
+
+        requestPromise.catch((err: MatrixError) => {
+            if (err.errcode == 'M_UNKNOWN_TOKEN' && !opts?.inhibitLogoutEmit) {
+                this.eventEmitter.emit(HttpApiEvent.SessionLoggedOut, err);
+            } else if (err.errcode == 'M_CONSENT_NOT_GIVEN') {
+                this.eventEmitter.emit(HttpApiEvent.NoConsent, err.message, err.data.consent_uri);
+            }
+        });
+
+        // return the original promise, otherwise tests break due to it having to
+        // go around the event loop one more time to process the result of the request
+        return requestPromise;
+    }
+
+    /**
+     * Perform a request to the homeserver without any credentials.
+     * @param {string} method The HTTP method e.g. "GET".
+     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
+     * "/createRoom".
+     *
+     * @param {Object=} queryParams A dict of query params (these will NOT be
+     * urlencoded). If unspecified, there will be no query params.
+     *
+     * @param {Object} [body] The HTTP JSON body.
+     *
+     * @param {Object=} opts additional options
+     *
+     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
+     * timing out the request. If not specified, there is no timeout.
+     *
+     * @param {string=} opts.prefix The full prefix to use e.g.
+     * "/_matrix/client/v2_alpha". If not specified, uses this.opts.prefix.
+     *
+     * @param {Object=} opts.headers map of additional request headers
+     *
+     * @return {Promise} Resolves to <code>{data: {Object},
+     * headers: {Object}, code: {Number}}</code>.
+     * If <code>onlyData</code> is set, this will resolve to the <code>data</code>
+     * object only.
+     * @return {module:http-api.MatrixError} Rejects with an error if a problem
+     * occurred. This includes network problems and Matrix-specific error JSON.
+     */
+    public request<T>(
+        method: Method,
+        path: string,
+        queryParams?: QueryDict,
+        body?: Body,
+        opts?: IRequestOpts,
+    ): Promise<ResponseType<T, O>> {
+        const fullUri = this.getUrl(path, queryParams, opts?.prefix, opts?.baseUrl);
+        return this.requestOtherUrl<T>(method, fullUri, body, opts);
+    }
+
+    /**
+     * Perform a request to an arbitrary URL.
+     * @param {string} method The HTTP method e.g. "GET".
+     * @param {string} url The HTTP URL object.
+     *
+     * @param {Object} [body] The HTTP JSON body.
+     *
+     * @param {Object=} opts additional options
+     *
+     * @param {Number=} opts.localTimeoutMs The maximum amount of time to wait before
+     * timing out the request. If not specified, there is no timeout.
+     *
+     * @param {Object=} opts.headers map of additional request headers
+     *
+     * @return {Promise} Resolves to data unless `onlyData` is specified as false,
+     * where the resolved value will be a fetch Response object.
+     * @return {module:http-api.MatrixError} Rejects with an error if a problem
+     * occurred. This includes network problems and Matrix-specific error JSON.
+     */
+    public async requestOtherUrl<T>(
+        method: Method,
+        url: URL | string,
+        body?: Body,
+        opts: Pick<IRequestOpts, "headers" | "json" | "localTimeoutMs" | "abortSignal"> = {},
+    ): Promise<ResponseType<T, O>> {
+        const headers = Object.assign({}, opts.headers || {});
+        const json = opts.json ?? true;
+        // We can't use getPrototypeOf here as objects made in other contexts e.g. over postMessage won't have same ref
+        const jsonBody = json && body?.constructor?.name === Object.name;
+
+        if (json) {
+            if (jsonBody && !headers["Content-Type"]) {
+                headers["Content-Type"] = "application/json";
+            }
+
+            if (!headers["Accept"]) {
+                headers["Accept"] = "application/json";
+            }
+        }
+
+        const timeout = opts.localTimeoutMs ?? this.opts.localTimeoutMs;
+        const signals = [
+            this.abortController.signal,
+        ];
+        if (timeout !== undefined) {
+            signals.push(timeoutSignal(timeout));
+        }
+        if (opts.abortSignal) {
+            signals.push(opts.abortSignal);
+        }
+
+        let data: BodyInit;
+        if (jsonBody) {
+            data = JSON.stringify(body);
+        } else {
+            data = body as BodyInit;
+        }
+
+        const { signal, cleanup } = anySignal(signals);
+
+        let res: Response;
+        try {
+            res = await this.fetch(url, {
+                signal,
+                method,
+                body: data,
+                headers,
+                mode: "cors",
+                redirect: "follow",
+                referrer: "",
+                referrerPolicy: "no-referrer",
+                cache: "no-cache",
+                credentials: "omit", // we send credentials via headers
+            });
+        } catch (e) {
+            if (e.name === "AbortError") {
+                throw e;
+            }
+            throw new ConnectionError("fetch failed", e);
+        } finally {
+            cleanup();
+        }
+
+        if (!res.ok) {
+            throw parseErrorResponse(res, await res.text());
+        }
+
+        if (this.opts.onlyData) {
+            return json ? res.json() : res.text();
+        }
+        return res as ResponseType<T, O>;
+    }
+
+    /**
+     * Form and return a homeserver request URL based on the given path params and prefix.
+     * @param {string} path The HTTP path <b>after</b> the supplied prefix e.g. "/createRoom".
+     * @param {Object} queryParams A dict of query params (these will NOT be urlencoded).
+     * @param {string} prefix The full prefix to use e.g. "/_matrix/client/v2_alpha", defaulting to this.opts.prefix.
+     * @param {string} baseUrl The baseUrl to use e.g. "https://matrix.org/", defaulting to this.opts.baseUrl.
+     * @return {string} URL
+     */
+    public getUrl(
+        path: string,
+        queryParams?: QueryDict,
+        prefix?: string,
+        baseUrl?: string,
+    ): URL {
+        const url = new URL((baseUrl ?? this.opts.baseUrl) + (prefix ?? this.opts.prefix) + path);
+        if (queryParams) {
+            utils.encodeParams(queryParams, url.searchParams);
+        }
+        return url;
+    }
+}
diff --git a/src/http-api/index.ts b/src/http-api/index.ts
new file mode 100644
index 00000000000..62e4b478e4a
--- /dev/null
+++ b/src/http-api/index.ts
@@ -0,0 +1,216 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { FetchHttpApi } from "./fetch";
+import { FileType, IContentUri, IHttpOpts, Upload, UploadOpts, UploadResponse } from "./interface";
+import { MediaPrefix } from "./prefix";
+import * as utils from "../utils";
+import * as callbacks from "../realtime-callbacks";
+import { Method } from "./method";
+import { ConnectionError, MatrixError } from "./errors";
+import { parseErrorResponse } from "./utils";
+
+export * from "./interface";
+export * from "./prefix";
+export * from "./errors";
+export * from "./method";
+export * from "./utils";
+
+export class MatrixHttpApi<O extends IHttpOpts> extends FetchHttpApi<O> {
+    private uploads: Upload[] = [];
+
+    /**
+     * Upload content to the homeserver
+     *
+     * @param {object} file The object to upload. On a browser, something that
+     *   can be sent to XMLHttpRequest.send (typically a File).  Under node.js,
+     *   a Buffer, String or ReadStream.
+     *
+     * @param {object} opts  options object
+     *
+     * @param {string=} opts.name   Name to give the file on the server. Defaults
+     *   to <tt>file.name</tt>.
+     *
+     * @param {boolean=} opts.includeFilename if false will not send the filename,
+     *   e.g for encrypted file uploads where filename leaks are undesirable.
+     *   Defaults to true.
+     *
+     * @param {string=} opts.type   Content-type for the upload. Defaults to
+     *   <tt>file.type</tt>, or <tt>application/octet-stream</tt>.
+     *
+     * @param {boolean=} opts.rawResponse Return the raw body, rather than
+     *   parsing the JSON. Defaults to false (except on node.js, where it
+     *   defaults to true for backwards compatibility).
+     *
+     * @param {boolean=} opts.onlyContentUri Just return the content URI,
+     *   rather than the whole body. Defaults to false (except on browsers,
+     *   where it defaults to true for backwards compatibility). Ignored if
+     *   opts.rawResponse is true.
+     *
+     * @param {Function=} opts.progressHandler Optional. Called when a chunk of
+     *    data has been uploaded, with an object containing the fields `loaded`
+     *    (number of bytes transferred) and `total` (total size, if known).
+     *
+     * @return {Promise} Resolves to response object, as
+     *    determined by this.opts.onlyData, opts.rawResponse, and
+     *    opts.onlyContentUri.  Rejects with an error (usually a MatrixError).
+     */
+    public uploadContent(file: FileType, opts: UploadOpts = {}): Promise<UploadResponse> {
+        const includeFilename = opts.includeFilename ?? true;
+        const abortController = opts.abortController ?? new AbortController();
+
+        // If the file doesn't have a mime type, use a default since the HS errors if we don't supply one.
+        const contentType = opts.type ?? (file as File).type ?? 'application/octet-stream';
+        const fileName = opts.name ?? (file as File).name;
+
+        const upload = {
+            loaded: 0,
+            total: 0,
+            abortController,
+        } as Upload;
+        const defer = utils.defer<UploadResponse>();
+
+        if (global.XMLHttpRequest) {
+            const xhr = new global.XMLHttpRequest();
+
+            const timeoutFn = function() {
+                xhr.abort();
+                defer.reject(new Error("Timeout"));
+            };
+
+            // set an initial timeout of 30s; we'll advance it each time we get a progress notification
+            let timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);
+
+            xhr.onreadystatechange = function() {
+                switch (xhr.readyState) {
+                    case global.XMLHttpRequest.DONE:
+                        callbacks.clearTimeout(timeoutTimer);
+                        try {
+                            if (xhr.status === 0) {
+                                throw new DOMException(xhr.statusText, "AbortError"); // mimic fetch API
+                            }
+                            if (!xhr.responseText) {
+                                throw new Error('No response body.');
+                            }
+
+                            if (xhr.status >= 400) {
+                                defer.reject(parseErrorResponse(xhr, xhr.responseText));
+                            } else {
+                                defer.resolve(JSON.parse(xhr.responseText));
+                            }
+                        } catch (err) {
+                            if (err.name === "AbortError") {
+                                defer.reject(err);
+                                return;
+                            }
+
+                            (<MatrixError>err).httpStatus = xhr.status;
+                            defer.reject(new ConnectionError("request failed", err));
+                        }
+                        break;
+                }
+            };
+
+            xhr.upload.onprogress = (ev: ProgressEvent) => {
+                callbacks.clearTimeout(timeoutTimer);
+                upload.loaded = ev.loaded;
+                upload.total = ev.total;
+                timeoutTimer = callbacks.setTimeout(timeoutFn, 30000);
+                opts.progressHandler?.({
+                    loaded: ev.loaded,
+                    total: ev.total,
+                });
+            };
+
+            const url = this.getUrl("/upload", undefined, MediaPrefix.R0);
+
+            if (includeFilename && fileName) {
+                url.searchParams.set("filename", encodeURIComponent(fileName));
+            }
+
+            if (!this.opts.useAuthorizationHeader && this.opts.accessToken) {
+                url.searchParams.set("access_token", encodeURIComponent(this.opts.accessToken));
+            }
+
+            xhr.open(Method.Post, url.href);
+            if (this.opts.useAuthorizationHeader && this.opts.accessToken) {
+                xhr.setRequestHeader("Authorization", "Bearer " + this.opts.accessToken);
+            }
+            xhr.setRequestHeader("Content-Type", contentType);
+            xhr.send(file);
+
+            abortController.signal.addEventListener("abort", () => {
+                xhr.abort();
+            });
+        } else {
+            const queryParams: utils.QueryDict = {};
+            if (includeFilename && fileName) {
+                queryParams.filename = fileName;
+            }
+
+            const headers: Record<string, string> = { "Content-Type": contentType };
+
+            this.authedRequest<UploadResponse>(
+                Method.Post, "/upload", queryParams, file, {
+                    prefix: MediaPrefix.R0,
+                    headers,
+                    abortSignal: abortController.signal,
+                },
+            ).then(response => {
+                return this.opts.onlyData ? <UploadResponse>response : response.json();
+            }).then(defer.resolve, defer.reject);
+        }
+
+        // remove the upload from the list on completion
+        upload.promise = defer.promise.finally(() => {
+            utils.removeElement(this.uploads, elem => elem === upload);
+        });
+        abortController.signal.addEventListener("abort", () => {
+            utils.removeElement(this.uploads, elem => elem === upload);
+            defer.reject(new DOMException("Aborted", "AbortError"));
+        });
+        this.uploads.push(upload);
+        return upload.promise;
+    }
+
+    public cancelUpload(promise: Promise<UploadResponse>): boolean {
+        const upload = this.uploads.find(u => u.promise === promise);
+        if (upload) {
+            upload.abortController.abort();
+            return true;
+        }
+        return false;
+    }
+
+    public getCurrentUploads(): Upload[] {
+        return this.uploads;
+    }
+
+    /**
+     * Get the content repository url with query parameters.
+     * @return {Object} An object with a 'base', 'path' and 'params' for base URL,
+     *          path and query parameters respectively.
+     */
+    public getContentUri(): IContentUri {
+        return {
+            base: this.opts.baseUrl,
+            path: MediaPrefix.R0 + "/upload",
+            params: {
+                access_token: this.opts.accessToken,
+            },
+        };
+    }
+}
diff --git a/src/http-api/interface.ts b/src/http-api/interface.ts
new file mode 100644
index 00000000000..c798bec0d6c
--- /dev/null
+++ b/src/http-api/interface.ts
@@ -0,0 +1,93 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { MatrixError } from "./errors";
+
+export interface IHttpOpts {
+    fetchFn?: typeof global.fetch;
+
+    baseUrl: string;
+    idBaseUrl?: string;
+    prefix: string;
+    extraParams?: Record<string, string>;
+
+    accessToken?: string;
+    useAuthorizationHeader?: boolean; // defaults to true
+
+    onlyData?: boolean;
+    localTimeoutMs?: number;
+}
+
+export interface IRequestOpts {
+    baseUrl?: string;
+    prefix?: string;
+
+    headers?: Record<string, string>;
+    abortSignal?: AbortSignal;
+    localTimeoutMs?: number;
+    json?: boolean; // defaults to true
+
+    // Set to true to prevent the request function from emitting a Session.logged_out event.
+    // This is intended for use on endpoints where M_UNKNOWN_TOKEN is a valid/notable error response,
+    // such as with token refreshes.
+    inhibitLogoutEmit?: boolean;
+}
+
+export interface IContentUri {
+    base: string;
+    path: string;
+    params: {
+        // eslint-disable-next-line camelcase
+        access_token: string;
+    };
+}
+
+export enum HttpApiEvent {
+    SessionLoggedOut = "Session.logged_out",
+    NoConsent = "no_consent",
+}
+
+export type HttpApiEventHandlerMap = {
+    [HttpApiEvent.SessionLoggedOut]: (err: MatrixError) => void;
+    [HttpApiEvent.NoConsent]: (message: string, consentUri: string) => void;
+};
+
+export interface UploadProgress {
+    loaded: number;
+    total: number;
+}
+
+export interface UploadOpts {
+    name?: string;
+    type?: string;
+    includeFilename?: boolean;
+    progressHandler?(progress: UploadProgress): void;
+    abortController?: AbortController;
+}
+
+export interface Upload {
+    loaded: number;
+    total: number;
+    promise: Promise<UploadResponse>;
+    abortController: AbortController;
+}
+
+export interface UploadResponse {
+    // eslint-disable-next-line camelcase
+    content_uri: string;
+}
+
+export type FileType = XMLHttpRequestBodyInit;
diff --git a/src/http-api/method.ts b/src/http-api/method.ts
new file mode 100644
index 00000000000..1914360e3a3
--- /dev/null
+++ b/src/http-api/method.ts
@@ -0,0 +1,22 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+export enum Method {
+    Get = "GET",
+    Put = "PUT",
+    Post = "POST",
+    Delete = "DELETE",
+}
diff --git a/src/http-api/prefix.ts b/src/http-api/prefix.ts
new file mode 100644
index 00000000000..8111bc3557a
--- /dev/null
+++ b/src/http-api/prefix.ts
@@ -0,0 +1,53 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+export enum ClientPrefix {
+    /**
+     * A constant representing the URI path for release 0 of the Client-Server HTTP API.
+     */
+    R0 = "/_matrix/client/r0",
+    /**
+     * A constant representing the URI path for the legacy release v1 of the Client-Server HTTP API.
+     */
+    V1 = "/_matrix/client/v1",
+    /**
+     * A constant representing the URI path for Client-Server API endpoints versioned at v3.
+     */
+    V3 = "/_matrix/client/v3",
+    /**
+     * A constant representing the URI path for as-yet unspecified Client-Server HTTP APIs.
+     */
+    Unstable = "/_matrix/client/unstable",
+}
+
+export enum IdentityPrefix {
+    /**
+     * URI path for v1 of the identity API
+     * @deprecated Use v2.
+     */
+    V1 = "/_matrix/identity/api/v1",
+    /**
+     * URI path for the v2 identity API
+     */
+    V2 = "/_matrix/identity/api/v2",
+}
+
+export enum MediaPrefix {
+    /**
+     * URI path for the media repo API
+     */
+    R0 = "/_matrix/media/r0",
+}
diff --git a/src/http-api/utils.ts b/src/http-api/utils.ts
new file mode 100644
index 00000000000..220e0300b05
--- /dev/null
+++ b/src/http-api/utils.ts
@@ -0,0 +1,149 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { parse as parseContentType, ParsedMediaType } from "content-type";
+
+import { logger } from "../logger";
+import { sleep } from "../utils";
+import { ConnectionError, MatrixError } from "./errors";
+
+// Ponyfill for https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal/timeout
+export function timeoutSignal(ms: number): AbortSignal {
+    const controller = new AbortController();
+    setTimeout(() => {
+        controller.abort();
+    }, ms);
+
+    return controller.signal;
+}
+
+export function anySignal(signals: AbortSignal[]): {
+    signal: AbortSignal;
+    cleanup(): void;
+} {
+    const controller = new AbortController();
+
+    function cleanup() {
+        for (const signal of signals) {
+            signal.removeEventListener("abort", onAbort);
+        }
+    }
+
+    function onAbort() {
+        controller.abort();
+        cleanup();
+    }
+
+    for (const signal of signals) {
+        if (signal.aborted) {
+            onAbort();
+            break;
+        }
+        signal.addEventListener("abort", onAbort);
+    }
+
+    return {
+        signal: controller.signal,
+        cleanup,
+    };
+}
+
+/**
+ * Attempt to turn an HTTP error response into a Javascript Error.
+ *
+ * If it is a JSON response, we will parse it into a MatrixError. Otherwise
+ * we return a generic Error.
+ *
+ * @param {XMLHttpRequest|Response} response response object
+ * @param {String} body raw body of the response
+ * @returns {Error}
+ */
+export function parseErrorResponse(response: XMLHttpRequest | Response, body?: string): Error {
+    let contentType: ParsedMediaType;
+    try {
+        contentType = getResponseContentType(response);
+    } catch (e) {
+        return e;
+    }
+
+    if (contentType?.type === "application/json" && body) {
+        return new MatrixError(JSON.parse(body), response.status);
+    }
+    if (contentType?.type === "text/plain") {
+        return new Error(`Server returned ${response.status} error: ${body}`);
+    }
+    return new Error(`Server returned ${response.status} error`);
+}
+
+function isXhr(response: XMLHttpRequest | Response): response is XMLHttpRequest {
+    return "getResponseHeader" in response;
+}
+
+/**
+ * extract the Content-Type header from the response object, and
+ * parse it to a `{type, parameters}` object.
+ *
+ * returns null if no content-type header could be found.
+ *
+ * @param {XMLHttpRequest|Response} response response object
+ * @returns {{type: String, parameters: Object}?} parsed content-type header, or null if not found
+ */
+function getResponseContentType(response: XMLHttpRequest | Response): ParsedMediaType | null {
+    let contentType: string | null;
+    if (isXhr(response)) {
+        contentType = response.getResponseHeader("Content-Type");
+    } else {
+        contentType = response.headers.get("Content-Type");
+    }
+
+    if (!contentType) return null;
+
+    try {
+        return parseContentType(contentType);
+    } catch (e) {
+        throw new Error(`Error parsing Content-Type '${contentType}': ${e}`);
+    }
+}
+
+/**
+ * Retries a network operation run in a callback.
+ * @param  {number}   maxAttempts maximum attempts to try
+ * @param  {Function} callback    callback that returns a promise of the network operation. If rejected with ConnectionError, it will be retried by calling the callback again.
+ * @return {any} the result of the network operation
+ * @throws {ConnectionError} If after maxAttempts the callback still throws ConnectionError
+ */
+export async function retryNetworkOperation<T>(maxAttempts: number, callback: () => Promise<T>): Promise<T> {
+    let attempts = 0;
+    let lastConnectionError: ConnectionError | null = null;
+    while (attempts < maxAttempts) {
+        try {
+            if (attempts > 0) {
+                const timeout = 1000 * Math.pow(2, attempts);
+                logger.log(`network operation failed ${attempts} times, retrying in ${timeout}ms...`);
+                await sleep(timeout);
+            }
+            return await callback();
+        } catch (err) {
+            if (err instanceof ConnectionError) {
+                attempts += 1;
+                lastConnectionError = err;
+            } else {
+                throw err;
+            }
+        }
+    }
+    throw lastConnectionError;
+}
diff --git a/src/index.ts b/src/index.ts
index c651438fb75..4b84224353f 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -14,17 +14,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import * as request from "request";
-
 import * as matrixcs from "./matrix";
 import * as utils from "./utils";
 import { logger } from './logger';
 
-if (matrixcs.getRequest()) {
+if (global.__js_sdk_entrypoint) {
     throw new Error("Multiple matrix-js-sdk entrypoints detected!");
 }
-
-matrixcs.request(request);
+global.__js_sdk_entrypoint = true;
 
 try {
     // eslint-disable-next-line @typescript-eslint/no-var-requires
diff --git a/src/matrix.ts b/src/matrix.ts
index 6813655a995..eaa9b09e76b 100644
--- a/src/matrix.ts
+++ b/src/matrix.ts
@@ -55,41 +55,6 @@ export {
     createNewMatrixCall,
 } from "./webrtc/call";
 
-// expose the underlying request object so different environments can use
-// different request libs (e.g. request or browser-request)
-let requestInstance;
-
-/**
- * The function used to perform HTTP requests. Only use this if you want to
- * use a different HTTP library, e.g. Angular's <code>$http</code>. This should
- * be set prior to calling {@link createClient}.
- * @param {requestFunction} r The request function to use.
- */
-export function request(r) {
-    requestInstance = r;
-}
-
-/**
- * Return the currently-set request function.
- * @return {requestFunction} The current request function.
- */
-export function getRequest() {
-    return requestInstance;
-}
-
-/**
- * Apply wrapping code around the request function. The wrapper function is
- * installed as the new request handler, and when invoked it is passed the
- * previous value, along with the options and callback arguments.
- * @param {requestWrapperFunction} wrapper The wrapping function.
- */
-export function wrapRequest(wrapper) {
-    const origRequest = requestInstance;
-    requestInstance = function(options, callback) {
-        return wrapper(origRequest, options, callback);
-    };
-}
-
 let cryptoStoreFactory = () => new MemoryCryptoStore;
 
 /**
@@ -128,15 +93,13 @@ export interface ICryptoCallbacks {
 /**
  * Construct a Matrix Client. Similar to {@link module:client.MatrixClient}
  * except that the 'request', 'store' and 'scheduler' dependencies are satisfied.
- * @param {(Object|string)} opts The configuration options for this client. If
+ * @param {(Object)} opts The configuration options for this client. If
  * this is a string, it is assumed to be the base URL. These configuration
  * options will be passed directly to {@link module:client.MatrixClient}.
  * @param {Object} opts.store If not set, defaults to
  * {@link module:store/memory.MemoryStore}.
  * @param {Object} opts.scheduler If not set, defaults to
  * {@link module:scheduler~MatrixScheduler}.
- * @param {requestFunction} opts.request If not set, defaults to the function
- * supplied to {@link request} which defaults to the request module from NPM.
  *
  * @param {module:crypto.store.base~CryptoStore=} opts.cryptoStore
  *    crypto store implementation. Calls the factory supplied to
@@ -148,13 +111,7 @@ export interface ICryptoCallbacks {
  * @see {@link module:client.MatrixClient} for the full list of options for
  * <code>opts</code>.
  */
-export function createClient(opts: ICreateClientOpts | string) {
-    if (typeof opts === "string") {
-        opts = {
-            "baseUrl": opts,
-        };
-    }
-    opts.request = opts.request || requestInstance;
+export function createClient(opts: ICreateClientOpts) {
     opts.store = opts.store || new MemoryStore({
         localStorage: global.localStorage,
     });
@@ -163,23 +120,6 @@ export function createClient(opts: ICreateClientOpts | string) {
     return new MatrixClient(opts);
 }
 
-/**
- * The request function interface for performing HTTP requests. This matches the
- * API for the {@link https://github.com/request/request#requestoptions-callback|
- * request NPM module}. The SDK will attempt to call this function in order to
- * perform an HTTP request.
- * @callback requestFunction
- * @param {Object} opts The options for this HTTP request.
- * @param {string} opts.uri The complete URI.
- * @param {string} opts.method The HTTP method.
- * @param {Object} opts.qs The query parameters to append to the URI.
- * @param {Object} opts.body The JSON-serializable object.
- * @param {boolean} opts.json True if this is a JSON request.
- * @param {Object} opts._matrix_opts The underlying options set for
- * {@link MatrixHttpApi}.
- * @param {requestCallback} callback The request callback.
- */
-
 /**
  * A wrapper for the request function interface.
  * @callback requestWrapperFunction
diff --git a/src/models/MSC3089TreeSpace.ts b/src/models/MSC3089TreeSpace.ts
index 0426d596e2e..9a9deec68ac 100644
--- a/src/models/MSC3089TreeSpace.ts
+++ b/src/models/MSC3089TreeSpace.ts
@@ -476,10 +476,8 @@ export class MSC3089TreeSpace {
         info: Partial<IEncryptedFile>,
         additionalContent?: IContent,
     ): Promise<ISendEventResponse> {
-        const mxc = await this.client.uploadContent(encryptedContents, {
+        const { content_uri: mxc } = await this.client.uploadContent(encryptedContents, {
             includeFilename: false,
-            onlyContentUri: true,
-            rawResponse: false, // make this explicit otherwise behaviour is different on browser vs NodeJS
         });
         info.url = mxc;
 
diff --git a/src/scheduler.ts b/src/scheduler.ts
index 271982b745a..2131e95c253 100644
--- a/src/scheduler.ts
+++ b/src/scheduler.ts
@@ -24,7 +24,7 @@ import { logger } from './logger';
 import { MatrixEvent } from "./models/event";
 import { EventType } from "./@types/event";
 import { IDeferred } from "./utils";
-import { MatrixError } from "./http-api";
+import { ConnectionError, MatrixError } from "./http-api";
 import { ISendEventResponse } from "./@types/requests";
 
 const DEBUG = false;  // set true to enable console logging.
@@ -68,9 +68,7 @@ export class MatrixScheduler<T = ISendEventResponse> {
             // client error; no amount of retrying with save you now.
             return -1;
         }
-        // we ship with browser-request which returns { cors: rejected } when trying
-        // with no connection, so if we match that, give up since they have no conn.
-        if (err["cors"] === "rejected") {
+        if (err instanceof ConnectionError) {
             return -1;
         }
 
diff --git a/src/sliding-sync-sdk.ts b/src/sliding-sync-sdk.ts
index 21d2af63f0d..e1072f8daa9 100644
--- a/src/sliding-sync-sdk.ts
+++ b/src/sliding-sync-sdk.ts
@@ -674,7 +674,7 @@ export class SlidingSyncSdk {
             member._requestedProfileInfo = true;
             // try to get a cached copy first.
             const user = client.getUser(member.userId);
-            let promise;
+            let promise: ReturnType<MatrixClient["getProfileInfo"]>;
             if (user) {
                 promise = Promise.resolve({
                     avatar_url: user.avatarUrl,
diff --git a/src/sliding-sync.ts b/src/sliding-sync.ts
index da6419c9676..5297ebd14b4 100644
--- a/src/sliding-sync.ts
+++ b/src/sliding-sync.ts
@@ -15,11 +15,11 @@ limitations under the License.
 */
 
 import { logger } from './logger';
-import { IAbortablePromise } from "./@types/partials";
 import { MatrixClient } from "./client";
 import { IRoomEvent, IStateEvent } from "./sync-accumulator";
-import { TypedEventEmitter } from "./models//typed-event-emitter";
+import { TypedEventEmitter } from "./models/typed-event-emitter";
 import { sleep, IDeferred, defer } from "./utils";
+import { ConnectionError } from "./http-api";
 
 // /sync requests allow you to set a timeout= but the request may continue
 // beyond that and wedge forever, so we need to track how long we are willing
@@ -353,7 +353,8 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
     private desiredRoomSubscriptions = new Set<string>(); // the *desired* room subscriptions
     private confirmedRoomSubscriptions = new Set<string>();
 
-    private pendingReq?: IAbortablePromise<MSC3575SlidingSyncResponse>;
+    private pendingReq?: Promise<MSC3575SlidingSyncResponse>;
+    private abortController?: AbortController;
 
     /**
      * Create a new sliding sync instance
@@ -700,7 +701,8 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
             ...d,
             txnId: this.txnId,
         });
-        this.pendingReq?.abort();
+        this.abortController?.abort();
+        this.abortController = new AbortController();
         return d.promise;
     }
 
@@ -728,7 +730,7 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
             this.txnIdDefers[i].reject(this.txnIdDefers[i].txnId);
         }
         this.txnIdDefers[txnIndex].resolve(txnId);
-        // clear out settled promises, incuding the one we resolved.
+        // clear out settled promises, including the one we resolved.
         this.txnIdDefers = this.txnIdDefers.slice(txnIndex+1);
     }
 
@@ -737,7 +739,7 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
      */
     public stop(): void {
         this.terminated = true;
-        this.pendingReq?.abort();
+        this.abortController?.abort();
         // remove all listeners so things can be GC'd
         this.removeAllListeners(SlidingSyncEvent.Lifecycle);
         this.removeAllListeners(SlidingSyncEvent.List);
@@ -748,6 +750,8 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
      * Start syncing with the server. Blocks until stopped.
      */
     public async start() {
+        this.abortController = new AbortController();
+
         let currentPos: string;
         while (!this.terminated) {
             this.needsResend = false;
@@ -780,7 +784,7 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
                     reqBody.txn_id = this.txnId;
                     this.txnId = null;
                 }
-                this.pendingReq = this.client.slidingSync(reqBody, this.proxyBaseUrl);
+                this.pendingReq = this.client.slidingSync(reqBody, this.proxyBaseUrl, this.abortController.signal);
                 resp = await this.pendingReq;
                 logger.debug(resp);
                 currentPos = resp.pos;
@@ -821,10 +825,7 @@ export class SlidingSync extends TypedEventEmitter<SlidingSyncEvent, SlidingSync
                         err,
                     );
                     await sleep(3000);
-                } else if (this.needsResend || err === "aborted") {
-                    // don't sleep as we caused this error by abort()ing the request.
-                    // we check for 'aborted' because that's the error Jest returns and without it
-                    // we get warnings about not exiting fast enough.
+                } else if (this.needsResend || err instanceof ConnectionError) {
                     continue;
                 } else {
                     logger.error(err);
diff --git a/src/store/index.ts b/src/store/index.ts
index 3645b598bae..4e99304fdcf 100644
--- a/src/store/index.ts
+++ b/src/store/index.ts
@@ -247,7 +247,7 @@ export interface IStore {
      /**
       * Fetches the oldest batch of to-device messages in the queue
       */
-     getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch>;
+     getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch | null>;
 
      /**
       * Removes a specific batch of to-device messages from the queue
diff --git a/src/store/indexeddb-backend.ts b/src/store/indexeddb-backend.ts
index 3a14fed7dee..f7547d6e531 100644
--- a/src/store/indexeddb-backend.ts
+++ b/src/store/indexeddb-backend.ts
@@ -33,7 +33,7 @@ export interface IIndexedDBBackend {
     getClientOptions(): Promise<IStartClientOpts>;
     storeClientOptions(options: IStartClientOpts): Promise<void>;
     saveToDeviceBatches(batches: ToDeviceBatchWithTxnId[]): Promise<void>;
-    getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch>;
+    getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch | null>;
     removeToDeviceBatch(id: number): Promise<void>;
 }
 
diff --git a/src/store/indexeddb-remote-backend.ts b/src/store/indexeddb-remote-backend.ts
index 8be023f2bc6..d36404b90df 100644
--- a/src/store/indexeddb-remote-backend.ts
+++ b/src/store/indexeddb-remote-backend.ts
@@ -138,7 +138,7 @@ export class RemoteIndexedDBStoreBackend implements IIndexedDBBackend {
         return this.doCmd('saveToDeviceBatches', [batches]);
     }
 
-    public async getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch> {
+    public async getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch | null> {
         return this.doCmd('getOldestToDeviceBatch');
     }
 
diff --git a/src/store/indexeddb.ts b/src/store/indexeddb.ts
index 44f684bdf8f..2bc4f28f6e5 100644
--- a/src/store/indexeddb.ts
+++ b/src/store/indexeddb.ts
@@ -357,7 +357,7 @@ export class IndexedDBStore extends MemoryStore {
         return this.backend.saveToDeviceBatches(batches);
     }
 
-    public getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch> {
+    public getOldestToDeviceBatch(): Promise<IndexedToDeviceBatch | null> {
         return this.backend.getOldestToDeviceBatch();
     }
 
diff --git a/src/sync.ts b/src/sync.ts
index cee5e7f09f4..60fb34aed7f 100644
--- a/src/sync.ts
+++ b/src/sync.ts
@@ -57,7 +57,6 @@ import { RoomStateEvent, IMarkerFoundOptions } from "./models/room-state";
 import { RoomMemberEvent } from "./models/room-member";
 import { BeaconEvent } from "./models/beacon";
 import { IEventsResponse } from "./@types/requests";
-import { IAbortablePromise } from "./@types/partials";
 import { UNREAD_THREAD_NOTIFICATIONS } from "./@types/sync";
 import { Feature, ServerSupport } from "./feature";
 
@@ -164,7 +163,8 @@ type WrappedRoom<T> = T & {
  */
 export class SyncApi {
     private _peekRoom: Optional<Room> = null;
-    private currentSyncRequest: Optional<IAbortablePromise<ISyncResponse>> = null;
+    private currentSyncRequest: Optional<Promise<ISyncResponse>> = null;
+    private abortController?: AbortController;
     private syncState: Optional<SyncState> = null;
     private syncStateData: Optional<ISyncStateData> = null; // additional data (eg. error object for failed sync)
     private catchingUp = false;
@@ -298,9 +298,9 @@ export class SyncApi {
             getFilterName(client.credentials.userId, "LEFT_ROOMS"), filter,
         ).then(function(filterId) {
             qps.filter = filterId;
-            return client.http.authedRequest<ISyncResponse>(
-                undefined, Method.Get, "/sync", qps as any, undefined, localTimeoutMs,
-            );
+            return client.http.authedRequest<ISyncResponse>(Method.Get, "/sync", qps as any, undefined, {
+                localTimeoutMs,
+            });
         }).then(async (data) => {
             let leaveRooms = [];
             if (data.rooms?.leave) {
@@ -433,11 +433,11 @@ export class SyncApi {
         }
 
         // FIXME: gut wrenching; hard-coded timeout values
-        this.client.http.authedRequest<IEventsResponse>(undefined, Method.Get, "/events", {
+        this.client.http.authedRequest<IEventsResponse>(Method.Get, "/events", {
             room_id: peekRoom.roomId,
             timeout: String(30 * 1000),
             from: token,
-        }, undefined, 50 * 1000).then((res) => {
+        }, undefined, { localTimeoutMs: 50 * 1000 }).then((res) => {
             if (this._peekRoom !== peekRoom) {
                 debuglog("Stopped peeking in room %s", peekRoom.roomId);
                 return;
@@ -652,6 +652,7 @@ export class SyncApi {
      */
     public async sync(): Promise<void> {
         this.running = true;
+        this.abortController = new AbortController();
 
         global.window?.addEventListener?.("online", this.onOnline, false);
 
@@ -738,7 +739,7 @@ export class SyncApi {
         // but do not have global.window.removeEventListener.
         global.window?.removeEventListener?.("online", this.onOnline, false);
         this.running = false;
-        this.currentSyncRequest?.abort();
+        this.abortController?.abort();
         if (this.keepAliveTimer) {
             clearTimeout(this.keepAliveTimer);
             this.keepAliveTimer = null;
@@ -902,12 +903,12 @@ export class SyncApi {
         }
     }
 
-    private doSyncRequest(syncOptions: ISyncOptions, syncToken: string): IAbortablePromise<ISyncResponse> {
+    private doSyncRequest(syncOptions: ISyncOptions, syncToken: string): Promise<ISyncResponse> {
         const qps = this.getSyncParams(syncOptions, syncToken);
-        return this.client.http.authedRequest<ISyncResponse>(
-            undefined, Method.Get, "/sync", qps as any, undefined,
-            qps.timeout + BUFFER_PERIOD_MS,
-        );
+        return this.client.http.authedRequest<ISyncResponse>(Method.Get, "/sync", qps as any, undefined, {
+            localTimeoutMs: qps.timeout + BUFFER_PERIOD_MS,
+            abortSignal: this.abortController?.signal,
+        });
     }
 
     private getSyncParams(syncOptions: ISyncOptions, syncToken: string): ISyncParams {
@@ -1521,7 +1522,6 @@ export class SyncApi {
         };
 
         this.client.http.request(
-            undefined, // callback
             Method.Get, "/_matrix/client/versions",
             undefined, // queryParams
             undefined, // data
diff --git a/src/utils.ts b/src/utils.ts
index e4b8b466e92..591803296f7 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -59,17 +59,23 @@ export function internaliseString(str: string): string {
  * {"foo": "bar", "baz": "taz"}
  * @return {string} The encoded string e.g. foo=bar&baz=taz
  */
-export function encodeParams(params: Record<string, string | number | boolean>): string {
-    const searchParams = new URLSearchParams();
+export function encodeParams(params: QueryDict, urlSearchParams?: URLSearchParams): URLSearchParams {
+    const searchParams = urlSearchParams ?? new URLSearchParams();
     for (const [key, val] of Object.entries(params)) {
         if (val !== undefined && val !== null) {
-            searchParams.set(key, String(val));
+            if (Array.isArray(val)) {
+                val.forEach(v => {
+                    searchParams.append(key, String(v));
+                });
+            } else {
+                searchParams.append(key, String(val));
+            }
         }
     }
-    return searchParams.toString();
+    return searchParams;
 }
 
-export type QueryDict = Record<string, string | string[]>;
+export type QueryDict = Record<string, string[] | string | number | boolean | undefined>;
 
 /**
  * Decode a query string in `application/x-www-form-urlencoded` format.
@@ -80,8 +86,8 @@ export type QueryDict = Record<string, string | string[]>;
  * This behaviour matches Node's qs.parse but is built on URLSearchParams
  * for native web compatibility
  */
-export function decodeParams(query: string): QueryDict {
-    const o: QueryDict = {};
+export function decodeParams(query: string): Record<string, string | string[]> {
+    const o: Record<string, string | string[]> = {};
     const params = new URLSearchParams(query);
     for (const key of params.keys()) {
         const val = params.getAll(key);
diff --git a/src/webrtc/call.ts b/src/webrtc/call.ts
index 90e20cc37ce..ad98e207910 100644
--- a/src/webrtc/call.ts
+++ b/src/webrtc/call.ts
@@ -298,7 +298,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
     // yet, null if we have but they didn't send a party ID.
     private opponentPartyId: string;
     private opponentCaps: CallCapabilities;
-    private inviteTimeout: ReturnType<typeof setTimeout>;
+    private inviteTimeout?: ReturnType<typeof setTimeout>;
 
     // The logic of when & if a call is on hold is nontrivial and explained in is*OnHold
     // This flag represents whether we want the other party to be on hold
@@ -322,7 +322,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
 
     private remoteSDPStreamMetadata: SDPStreamMetadata;
 
-    private callLengthInterval: ReturnType<typeof setInterval>;
+    private callLengthInterval?: ReturnType<typeof setInterval>;
     private callLength = 0;
 
     constructor(opts: CallOpts) {
@@ -1689,7 +1689,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
             this.inviteOrAnswerSent = true;
             this.setState(CallState.InviteSent);
             this.inviteTimeout = setTimeout(() => {
-                this.inviteTimeout = null;
+                this.inviteTimeout = undefined;
                 if (this.state === CallState.InviteSent) {
                     this.hangup(CallErrorCode.InviteTimeout, false);
                 }
@@ -2004,11 +2004,11 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
 
         if (this.inviteTimeout) {
             clearTimeout(this.inviteTimeout);
-            this.inviteTimeout = null;
+            this.inviteTimeout = undefined;
         }
         if (this.callLengthInterval) {
             clearInterval(this.callLengthInterval);
-            this.callLengthInterval = null;
+            this.callLengthInterval = undefined;
         }
 
         // Order is important here: first we stopAllMedia() and only then we can deleteAllFeeds()
diff --git a/yarn.lock b/yarn.lock
index bf9525555a5..bb4d5480212 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1588,16 +1588,18 @@
   dependencies:
     base-x "^3.0.6"
 
-"@types/caseless@*":
-  version "0.12.2"
-  resolved "https://registry.yarnpkg.com/@types/caseless/-/caseless-0.12.2.tgz#f65d3d6389e01eeb458bd54dc8f52b95a9463bc8"
-  integrity sha512-6ckxMjBBD8URvjB6J3NcnuAn5Pkl7t3TizAg+xdlzzQGSPSmBcXf8KoIH0ua/i+tio+ZRUHEXp0HEmvaR4kt0w==
-
 "@types/content-type@^1.1.5":
   version "1.1.5"
   resolved "https://registry.yarnpkg.com/@types/content-type/-/content-type-1.1.5.tgz#aa02dca40864749a9e2bf0161a6216da57e3ede5"
   integrity sha512-dgMN+syt1xb7Hk8LU6AODOfPlvz5z1CbXpPuJE5ZrX9STfBOIXF09pEB8N7a97WT9dbngt3ksDCm6GW6yMrxfQ==
 
+"@types/domexception@^4.0.0":
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/@types/domexception/-/domexception-4.0.0.tgz#bb19c920c81c3f1408b46d021fb79467ff2d32fd"
+  integrity sha512-vD9eLiVhgDrsVtUIiHBaToW/lfhCUYzmb81Sc0a0kJ4qEN2ZJyhz4wVyAmum4hAVDuBMUDE4yAeeF7fPHKCujw==
+  dependencies:
+    "@types/webidl-conversions" "*"
+
 "@types/graceful-fs@^4.1.3":
   version "4.1.5"
   resolved "https://registry.yarnpkg.com/@types/graceful-fs/-/graceful-fs-4.1.5.tgz#21ffba0d98da4350db64891f92a9e5db3cdb4e15"
@@ -1675,16 +1677,6 @@
   resolved "https://registry.yarnpkg.com/@types/prettier/-/prettier-2.7.1.tgz#dfd20e2dc35f027cdd6c1908e80a5ddc7499670e"
   integrity sha512-ri0UmynRRvZiiUJdiz38MmIblKK+oH30MztdBVR95dv/Ubw6neWSb8u1XpRb72L4qsZOhz+L+z9JD40SJmfWow==
 
-"@types/request@^2.48.5":
-  version "2.48.8"
-  resolved "https://registry.yarnpkg.com/@types/request/-/request-2.48.8.tgz#0b90fde3b655ab50976cb8c5ac00faca22f5a82c"
-  integrity sha512-whjk1EDJPcAR2kYHRbFl/lKeeKYTi05A15K9bnLInCVroNDCtXce57xKdI0/rQaA3K+6q0eFyUBPmqfSndUZdQ==
-  dependencies:
-    "@types/caseless" "*"
-    "@types/node" "*"
-    "@types/tough-cookie" "*"
-    form-data "^2.5.0"
-
 "@types/retry@0.12.0":
   version "0.12.0"
   resolved "https://registry.yarnpkg.com/@types/retry/-/retry-0.12.0.tgz#2b35eccfcee7d38cd72ad99232fbd58bffb3c84d"
@@ -1695,10 +1687,10 @@
   resolved "https://registry.yarnpkg.com/@types/stack-utils/-/stack-utils-2.0.1.tgz#20f18294f797f2209b5f65c8e3b5c8e8261d127c"
   integrity sha512-Hl219/BT5fLAaz6NDkSuhzasy49dwQS/DSdu4MdggFB8zcXv7vflBI3xp7FEmkmdDkBUI2bPUNeMttp2knYdxw==
 
-"@types/tough-cookie@*":
-  version "4.0.2"
-  resolved "https://registry.yarnpkg.com/@types/tough-cookie/-/tough-cookie-4.0.2.tgz#6286b4c7228d58ab7866d19716f3696e03a09397"
-  integrity sha512-Q5vtl1W5ue16D+nIaW8JWebSSraJVlK+EthKn7e7UcD4KWsaSJ8BqGPXNaPghgtcn/fhvrN17Tv8ksUsQpiplw==
+"@types/webidl-conversions@*":
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/@types/webidl-conversions/-/webidl-conversions-7.0.0.tgz#2b8e60e33906459219aa587e9d1a612ae994cfe7"
+  integrity sha512-xTE1E+YF4aWPJJeUzaZI5DRntlkY3+BCVJi0axFptnjGmAoWxkyREIh/XMrfxVLejwQxMCfDXdICo0VLxThrog==
 
 "@types/yargs-parser@*":
   version "21.0.0"
@@ -1858,7 +1850,7 @@ acorn@^8.5.0, acorn@^8.8.0:
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-8.8.0.tgz#88c0187620435c7f6015803f5539dae05a9dbea8"
   integrity sha512-QOxyigPVrpZ2GXT+PFyZTl6TtOFc5egxHIP9IlQ+RbupQuX4RkT/Bee4/kQuC02Xkzg84JcT7oLYtDIQxp+v7w==
 
-ajv@^6.10.0, ajv@^6.12.3, ajv@^6.12.4:
+ajv@^6.10.0, ajv@^6.12.4:
   version "6.12.6"
   resolved "https://registry.yarnpkg.com/ajv/-/ajv-6.12.6.tgz#baf5a62e802b07d977034586f8c3baf5adf26df4"
   integrity sha512-j3fVLgvTo527anyYyJOGTYJbG+vnnQYvE0m5mmkc1TK+nxAppkCLMIL0aZ4dblVCNoGShhm+kzE4ZUykBoMg4g==
@@ -1993,18 +1985,6 @@ asn1.js@^5.2.0:
     minimalistic-assert "^1.0.0"
     safer-buffer "^2.1.0"
 
-asn1@~0.2.3:
-  version "0.2.6"
-  resolved "https://registry.yarnpkg.com/asn1/-/asn1-0.2.6.tgz#0d3a7bb6e64e02a90c0303b31f292868ea09a08d"
-  integrity sha512-ix/FxPn0MDjeyJ7i/yoHGFt/EX6LyNbxSEhPPXODPL+KB0VPk86UYfL0lMdy+KCnv+fmvIzySwaK5COwqVbWTQ==
-  dependencies:
-    safer-buffer "~2.1.0"
-
-assert-plus@1.0.0, assert-plus@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/assert-plus/-/assert-plus-1.0.0.tgz#f12e0f3c5d77b0b1cdd9146942e4e96c1e4dd525"
-  integrity sha512-NfJ4UzBCcQGLDlQq7nHxH+tv3kyZ0hHQqF5BO6J7tNJeP5do1llPr8dZ8zHonfhAu0PHAdMkSo+8o0wxg9lZWw==
-
 assert@^1.4.0:
   version "1.5.0"
   resolved "https://registry.yarnpkg.com/assert/-/assert-1.5.0.tgz#55c109aaf6e0aefdb3dc4b71240c70bf574b18eb"
@@ -2025,26 +2005,11 @@ ast-types@^0.14.2:
   dependencies:
     tslib "^2.0.1"
 
-asynckit@^0.4.0:
-  version "0.4.0"
-  resolved "https://registry.yarnpkg.com/asynckit/-/asynckit-0.4.0.tgz#c79ed97f7f34cb8f2ba1bc9790bcc366474b4b79"
-  integrity sha512-Oei9OH4tRh0YqU3GxhX79dM/mwVgvbZJaSNaRk+bshkj0S5cfHcgYakreBjrHwatXKbz+IoIdYLxrKim2MjW0Q==
-
 available-typed-arrays@^1.0.5:
   version "1.0.5"
   resolved "https://registry.yarnpkg.com/available-typed-arrays/-/available-typed-arrays-1.0.5.tgz#92f95616501069d07d10edb2fc37d3e1c65123b7"
   integrity sha512-DMD0KiN46eipeziST1LPP/STfDU0sufISXmjSgvVsoU2tqxctQeASejWcfNtxYKqETM1UxQ8sp2OrSBWpHY6sw==
 
-aws-sign2@~0.7.0:
-  version "0.7.0"
-  resolved "https://registry.yarnpkg.com/aws-sign2/-/aws-sign2-0.7.0.tgz#b46e890934a9591f2d2f6f86d7e6a9f1b3fe76a8"
-  integrity sha512-08kcGqnYf/YmjoRhfxyu+CLxBjUtHLXLXX/vUfx9l2LYzG3c1m61nrpyFUZI6zeS+Li/wWMMidD9KgrqtGq3mA==
-
-aws4@^1.8.0:
-  version "1.11.0"
-  resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.11.0.tgz#d61f46d83b2519250e2784daf5b09479a8b41c59"
-  integrity sha512-xh1Rl34h6Fi1DC2WWKfxUTVqRsNnr6LsKz2+hfwDxQJWmrx8+c7ylaqBMcHfl1U1r2dsifOvKX3LQuLNZ+XSvA==
-
 babel-jest@^29.0.0, babel-jest@^29.1.2:
   version "29.1.2"
   resolved "https://registry.yarnpkg.com/babel-jest/-/babel-jest-29.1.2.tgz#540d3241925c55240fb0c742e3ffc5f33a501978"
@@ -2191,13 +2156,6 @@ base64-js@^1.0.2:
   resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.5.1.tgz#1b1b440160a5bf7ad40b650f095963481903930a"
   integrity sha512-AKpaYlHn8t4SVbOHCy+b5+KKgvR4vrsD8vbvrbiQJps7fKDTkjkDry6ji0rUJjC0kzbNePLwzxq8iypo41qeWA==
 
-bcrypt-pbkdf@^1.0.0:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/bcrypt-pbkdf/-/bcrypt-pbkdf-1.0.2.tgz#a4301d389b6a43f9b67ff3ca11a3f6637e360e9e"
-  integrity sha512-qeFIXtP4MSoi6NLqO12WfqARWWuCKi2Rn/9hJLEmtB5yTNr9DqFWkJRCf2qShWzPeAMRnOgCrq0sg/KLv5ES9w==
-  dependencies:
-    tweetnacl "^0.14.3"
-
 before-after-hook@^2.2.0:
   version "2.2.2"
   resolved "https://registry.yarnpkg.com/before-after-hook/-/before-after-hook-2.2.2.tgz#a6e8ca41028d90ee2c24222f201c90956091613e"
@@ -2274,11 +2232,6 @@ browser-pack@^6.0.1:
     through2 "^2.0.0"
     umd "^3.0.0"
 
-browser-request@^0.3.3:
-  version "0.3.3"
-  resolved "https://registry.yarnpkg.com/browser-request/-/browser-request-0.3.3.tgz#9ece5b5aca89a29932242e18bf933def9876cc17"
-  integrity sha512-YyNI4qJJ+piQG6MMEuo7J3Bzaqssufx04zpEKYfSrl/1Op59HWali9zMtBpXnkmqMcOuWJPZvudrm9wISmnCbg==
-
 browser-resolve@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/browser-resolve/-/browser-resolve-2.0.0.tgz#99b7304cb392f8d73dba741bb2d7da28c6d7842b"
@@ -2504,11 +2457,6 @@ caniuse-lite@^1.0.30001400:
   resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30001414.tgz#5f1715e506e71860b4b07c50060ea6462217611e"
   integrity sha512-t55jfSaWjCdocnFdKQoO+d2ct9C59UZg4dY3OnUlSZ447r8pUtIKdp0hpAzrGFultmTC+Us+KpKi4GZl/LXlFg==
 
-caseless@~0.12.0:
-  version "0.12.0"
-  resolved "https://registry.yarnpkg.com/caseless/-/caseless-0.12.0.tgz#1b681c21ff84033c826543090689420d187151dc"
-  integrity sha512-4tYFyifaFfGacoiObjJegolkwSU4xQNGbVgUiNYVUxbQ2x2lUsFvY4hVgVzGiIe6WLOPqycWXA40l+PWsxthUw==
-
 catharsis@^0.9.0:
   version "0.9.0"
   resolved "https://registry.yarnpkg.com/catharsis/-/catharsis-0.9.0.tgz#40382a168be0e6da308c277d3a2b3eb40c7d2121"
@@ -2684,13 +2632,6 @@ combine-source-map@^0.8.0, combine-source-map@~0.8.0:
     lodash.memoize "~3.0.3"
     source-map "~0.5.3"
 
-combined-stream@^1.0.6, combined-stream@~1.0.6:
-  version "1.0.8"
-  resolved "https://registry.yarnpkg.com/combined-stream/-/combined-stream-1.0.8.tgz#c3d45a8b34fd730631a110a8a2520682b31d5a7f"
-  integrity sha512-FQN4MRfuJeHf7cBbBMJFXhKSDq+2kAArBlmRBvcvFE5BB1HZKXtSFASDhdlz9zOYwxh8lDdnvmMOe/+5cdoEdg==
-  dependencies:
-    delayed-stream "~1.0.0"
-
 commander@^2.19.0, commander@^2.20.0:
   version "2.20.3"
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
@@ -2770,11 +2711,6 @@ core-js@^2.4.0:
   resolved "https://registry.yarnpkg.com/core-js/-/core-js-2.6.12.tgz#d9333dfa7b065e347cc5682219d6f690859cc2ec"
   integrity sha512-Kb2wC0fvsWfQrgk8HU5lW6U/Lcs8+9aaYcy4ZFc6DDlo4nZ7n70dEgE5rtR0oG6ufKDUnrwfWL1mXR5ljDatrQ==
 
-core-util-is@1.0.2:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.2.tgz#b5fd54220aa2bc5ab57aab7140c940754503c1a7"
-  integrity sha512-3lqz5YjWTYnW6dlDa5TLaTCcShfar1e40rmcJVwCBJC6mWlFuj0eCHIElmG1g5kyuJ/GD+8Wn4FFCcz4gJPfaQ==
-
 core-util-is@~1.0.0:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/core-util-is/-/core-util-is-1.0.3.tgz#a6042d3634c2b27e9328f837b965fac83808db85"
@@ -2850,13 +2786,6 @@ dash-ast@^1.0.0:
   resolved "https://registry.yarnpkg.com/dash-ast/-/dash-ast-1.0.0.tgz#12029ba5fb2f8aa6f0a861795b23c1b4b6c27d37"
   integrity sha512-Vy4dx7gquTeMcQR/hDkYLGUnwVil6vk4FOOct+djUnHOUWt+zJPJAaRIXaAFkPXtJjvlY7o3rfRu0/3hpnwoUA==
 
-dashdash@^1.12.0:
-  version "1.14.1"
-  resolved "https://registry.yarnpkg.com/dashdash/-/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
-  integrity sha512-jRFi8UDGo6j+odZiEpjazZaWqEal3w/basFjQHQEwVtZJGDpxbH1MeYluwCS8Xq5wmLJooDlMgvVarmWfGM44g==
-  dependencies:
-    assert-plus "^1.0.0"
-
 de-indent@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/de-indent/-/de-indent-1.0.2.tgz#b2038e846dc33baa5796128d0804b455b8c1e21d"
@@ -2921,11 +2850,6 @@ defined@^1.0.0:
   resolved "https://registry.yarnpkg.com/defined/-/defined-1.0.0.tgz#c98d9bcef75674188e110969151199e39b1fa693"
   integrity sha512-Y2caI5+ZwS5c3RiNDJ6u53VhQHv+hHKwhkI1iHvceKUHw9Df6EK2zRLfjejRgMuCuxK7PfSWIMwWecceVvThjQ==
 
-delayed-stream@~1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/delayed-stream/-/delayed-stream-1.0.0.tgz#df3ae199acadfb7d440aaae0b29e2272b24ec619"
-  integrity sha512-ZySD7Nf91aLB0RxL4KGrKHBXl7Eds1DAmEdcoVawXnLD7SDhpNgtuII2aAkg7a7QS41jxPSZ17p4VdGnMHk3MQ==
-
 deprecation@^2.0.0, deprecation@^2.3.1:
   version "2.3.1"
   resolved "https://registry.yarnpkg.com/deprecation/-/deprecation-2.3.1.tgz#6368cbdb40abf3373b525ac87e4a260c3a700919"
@@ -3030,6 +2954,13 @@ domexception@^1.0.1:
   dependencies:
     webidl-conversions "^4.0.2"
 
+domexception@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/domexception/-/domexception-4.0.0.tgz#4ad1be56ccadc86fc76d033353999a8037d03673"
+  integrity sha512-A2is4PLG+eeSfoTMA95/s4pvAoSo2mKtiM5jlHkAVewmiO8ISFTFKZjH7UAM1Atli/OT/7JHOrJRJiMKUZKYBw==
+  dependencies:
+    webidl-conversions "^7.0.0"
+
 duplexer2@^0.1.2, duplexer2@~0.1.0, duplexer2@~0.1.2:
   version "0.1.4"
   resolved "https://registry.yarnpkg.com/duplexer2/-/duplexer2-0.1.4.tgz#8b12dab878c0d69e3e7891051662a32fc6bddcc1"
@@ -3037,14 +2968,6 @@ duplexer2@^0.1.2, duplexer2@~0.1.0, duplexer2@~0.1.2:
   dependencies:
     readable-stream "^2.0.2"
 
-ecc-jsbn@~0.1.1:
-  version "0.1.2"
-  resolved "https://registry.yarnpkg.com/ecc-jsbn/-/ecc-jsbn-0.1.2.tgz#3a83a904e54353287874c564b7549386849a98c9"
-  integrity sha512-eh9O+hwRHNbG4BLTjEl3nw044CkGm5X6LoaCf7LPp7UU8Qrt47JYNi6nPX8xjW97TKGKm1ouctg0QSpZe9qrnw==
-  dependencies:
-    jsbn "~0.1.0"
-    safer-buffer "^2.1.0"
-
 electron-to-chromium@^1.4.251:
   version "1.4.270"
   resolved "https://registry.yarnpkg.com/electron-to-chromium/-/electron-to-chromium-1.4.270.tgz#2c6ea409b45cdb5c3e0cb2c08cf6c0ba7e0f2c26"
@@ -3467,21 +3390,6 @@ ext@^1.1.2:
   dependencies:
     type "^2.7.2"
 
-extend@~3.0.2:
-  version "3.0.2"
-  resolved "https://registry.yarnpkg.com/extend/-/extend-3.0.2.tgz#f8b1136b4071fbd8eb140aff858b1019ec2915fa"
-  integrity sha512-fjquC59cD7CyW6urNXK0FBufkZcoiGG80wTuPujX590cB5Ttln20E2UB4S/WARVqhXffZl2LNgS+gQdPIIim/g==
-
-extsprintf@1.3.0:
-  version "1.3.0"
-  resolved "https://registry.yarnpkg.com/extsprintf/-/extsprintf-1.3.0.tgz#96918440e3041a7a414f8c52e3c574eb3c3e1e05"
-  integrity sha512-11Ndz7Nv+mvAC1j0ktTa7fAb0vLyGGX+rMHNBYQviQDGU0Hw7lhctJANqbPhu9nV9/izT/IntTgZ7Im/9LJs9g==
-
-extsprintf@^1.2.0:
-  version "1.4.1"
-  resolved "https://registry.yarnpkg.com/extsprintf/-/extsprintf-1.4.1.tgz#8d172c064867f235c0c84a596806d279bf4bcc07"
-  integrity sha512-Wrk35e8ydCKDj/ArClo1VrPVmN8zph5V4AtHwIuHhvMXsKf73UT3BOD+azBIW+3wOJ4FhEH7zyaJCFvChjYvMA==
-
 fake-indexeddb@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/fake-indexeddb/-/fake-indexeddb-4.0.0.tgz#1dfb2023a3be175e35a6d84975218b432041934d"
@@ -3608,29 +3516,6 @@ foreground-child@^2.0.0:
     cross-spawn "^7.0.0"
     signal-exit "^3.0.2"
 
-forever-agent@~0.6.1:
-  version "0.6.1"
-  resolved "https://registry.yarnpkg.com/forever-agent/-/forever-agent-0.6.1.tgz#fbc71f0c41adeb37f96c577ad1ed42d8fdacca91"
-  integrity sha512-j0KLYPhm6zeac4lz3oJ3o65qvgQCcPubiyotZrXqEaG4hNagNYO8qdlUrX5vwqv9ohqeT/Z3j6+yW067yWWdUw==
-
-form-data@^2.5.0:
-  version "2.5.1"
-  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.5.1.tgz#f2cbec57b5e59e23716e128fe44d4e5dd23895f4"
-  integrity sha512-m21N3WOmEEURgk6B9GLOE4RuWOFf28Lhh9qGYeNlGq4VDXUlJy2th2slBNU8Gp8EzloYZOibZJ7t5ecIrFSjVA==
-  dependencies:
-    asynckit "^0.4.0"
-    combined-stream "^1.0.6"
-    mime-types "^2.1.12"
-
-form-data@~2.3.2:
-  version "2.3.3"
-  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.3.3.tgz#dcce52c05f644f298c6a7ab936bd724ceffbf3a6"
-  integrity sha512-1lLKB2Mu3aGP1Q/2eCOx0fNbRMe7XdwktwOruhfqqd0rIJWwN4Dh+E3hrPSlDCXnSR7UtZ1N38rVXm+6+MEhJQ==
-  dependencies:
-    asynckit "^0.4.0"
-    combined-stream "^1.0.6"
-    mime-types "^2.1.12"
-
 fs-readdir-recursive@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/fs-readdir-recursive/-/fs-readdir-recursive-1.1.0.tgz#e32fc030a2ccee44a6b5371308da54be0b397d27"
@@ -3713,13 +3598,6 @@ get-tsconfig@^4.2.0:
   resolved "https://registry.yarnpkg.com/get-tsconfig/-/get-tsconfig-4.2.0.tgz#ff368dd7104dab47bf923404eb93838245c66543"
   integrity sha512-X8u8fREiYOE6S8hLbq99PeykTDoLVnxvF4DjWKJmz9xy2nNRdUcV8ZN9tniJFeKyTU3qnC9lL8n4Chd6LmVKHg==
 
-getpass@^0.1.1:
-  version "0.1.7"
-  resolved "https://registry.yarnpkg.com/getpass/-/getpass-0.1.7.tgz#5eff8e3e684d569ae4cb2b1282604e8ba62149fa"
-  integrity sha512-0fzj9JxOLfJ+XGLhR8ze3unN0KZCgZwiSSDz168VERjK8Wl8kVSdcu2kspd4s4wtAa1y/qrVRiAA0WclVsu0ng==
-  dependencies:
-    assert-plus "^1.0.0"
-
 glob-parent@^5.1.2, glob-parent@~5.1.2:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/glob-parent/-/glob-parent-5.1.2.tgz#869832c58034fe68a4093c17dc15e8340d8401c4"
@@ -3801,19 +3679,6 @@ grapheme-splitter@^1.0.4:
   resolved "https://registry.yarnpkg.com/grapheme-splitter/-/grapheme-splitter-1.0.4.tgz#9cf3a665c6247479896834af35cf1dbb4400767e"
   integrity sha512-bzh50DW9kTPM00T8y4o8vQg89Di9oLJVLW/KaOGIXJWP/iqCN6WKYkbNOF04vFLJhwcpYUh9ydh/+5vpOqV4YQ==
 
-har-schema@^2.0.0:
-  version "2.0.0"
-  resolved "https://registry.yarnpkg.com/har-schema/-/har-schema-2.0.0.tgz#a94c2224ebcac04782a0d9035521f24735b7ec92"
-  integrity sha512-Oqluz6zhGX8cyRaTQlFMPw80bSJVG2x/cFb8ZPhUILGgHka9SsokCCOQgpveePerqidZOrT14ipqfJb7ILcW5Q==
-
-har-validator@~5.1.3:
-  version "5.1.5"
-  resolved "https://registry.yarnpkg.com/har-validator/-/har-validator-5.1.5.tgz#1f0803b9f8cb20c0fa13822df1ecddb36bde1efd"
-  integrity sha512-nmT2T0lljbxdQZfspsno9hgrG3Uir6Ks5afism62poxqBM6sDnMEuPmzTq8XN0OEwqKLLdh1jQI3qyE66Nzb3w==
-  dependencies:
-    ajv "^6.12.3"
-    har-schema "^2.0.0"
-
 has-bigints@^1.0.1, has-bigints@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/has-bigints/-/has-bigints-1.0.2.tgz#0871bd3e3d51626f6ca0966668ba35d5602d6eaa"
@@ -3901,15 +3766,6 @@ htmlescape@^1.1.0:
   resolved "https://registry.yarnpkg.com/htmlescape/-/htmlescape-1.1.1.tgz#3a03edc2214bca3b66424a3e7959349509cb0351"
   integrity sha512-eVcrzgbR4tim7c7soKQKtxa/kQM4TzjnlU83rcZ9bHU6t31ehfV7SktN6McWgwPWg+JYMA/O3qpGxBvFq1z2Jg==
 
-http-signature@~1.2.0:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/http-signature/-/http-signature-1.2.0.tgz#9aecd925114772f3d95b65a60abb8f7c18fbace1"
-  integrity sha512-CAbnr6Rz4CYQkLYUtSNXxQPUH2gK8f3iWexVlsnMeD+GjlsQ0Xsy1cOX+mN3dtxYomRy21CiOzU8Uhw6OwncEQ==
-  dependencies:
-    assert-plus "^1.0.0"
-    jsprim "^1.2.2"
-    sshpk "^1.7.0"
-
 https-browserify@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/https-browserify/-/https-browserify-1.0.0.tgz#ec06c10e0a34c0f2faf199f7fd7fc78fffd03c73"
@@ -4181,11 +4037,6 @@ is-typed-array@^1.1.3, is-typed-array@^1.1.9:
     for-each "^0.3.3"
     has-tostringtag "^1.0.0"
 
-is-typedarray@~1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/is-typedarray/-/is-typedarray-1.0.0.tgz#e479c80858df0c1b11ddda6940f96011fcda4a9a"
-  integrity sha512-cyA56iCMHAh5CdzjJIa4aohJyeO1YbwLi3Jc35MmRU6poroFjIGZzUzupGiRPOjgHg9TLu43xbpwXk523fMxKA==
-
 is-utf8@^0.2.0:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/is-utf8/-/is-utf8-0.2.1.tgz#4b0da1442104d1b336340e80797e865cf39f7d72"
@@ -4220,11 +4071,6 @@ isobject@^3.0.1:
   resolved "https://registry.yarnpkg.com/isobject/-/isobject-3.0.1.tgz#4e431e92b11a9731636aa1f9c8d1ccbcfdab78df"
   integrity sha512-WhB9zCku7EGTj/HQQRz5aUQEUeoQZH2bWcltRErOpymJ4boYE6wL9Tbr23krRPSZ+C5zqNSrSw+Cc7sZZ4b7vg==
 
-isstream@~0.1.2:
-  version "0.1.2"
-  resolved "https://registry.yarnpkg.com/isstream/-/isstream-0.1.2.tgz#47e63f7af55afa6f92e1500e690eb8b8529c099a"
-  integrity sha512-Yljz7ffyPbrLpLngrMtZ7NduUgVvi6wG9RJ9IUcyCd59YQ911PBJphODUcbOVbqYfxe1wuYf/LJ8PauMRwsM/g==
-
 istanbul-lib-coverage@^3.0.0, istanbul-lib-coverage@^3.2.0:
   version "3.2.0"
   resolved "https://registry.yarnpkg.com/istanbul-lib-coverage/-/istanbul-lib-coverage-3.2.0.tgz#189e7909d0a39fa5a3dfad5b03f71947770191d3"
@@ -4737,11 +4583,6 @@ js2xmlparser@^4.0.2:
   dependencies:
     xmlcreate "^2.0.4"
 
-jsbn@~0.1.0:
-  version "0.1.1"
-  resolved "https://registry.yarnpkg.com/jsbn/-/jsbn-0.1.1.tgz#a5e654c2e5a2deb5f201d96cefbca80c0ef2f513"
-  integrity sha512-UVU9dibq2JcFWxQPA6KCqj5O42VOmAY3zQUfEKxU0KpTGXwNoCjkX1e13eHNvw/xPynt6pU0rZ1htjWTNTSXsg==
-
 jsdoc@^3.6.6:
   version "3.6.11"
   resolved "https://registry.yarnpkg.com/jsdoc/-/jsdoc-3.6.11.tgz#8bbb5747e6f579f141a5238cbad4e95e004458ce"
@@ -4783,21 +4624,11 @@ json-schema-traverse@^0.4.1:
   resolved "https://registry.yarnpkg.com/json-schema-traverse/-/json-schema-traverse-0.4.1.tgz#69f6a87d9513ab8bb8fe63bdb0979c448e684660"
   integrity sha512-xbbCH5dCYU5T8LcEhhuh7HJ88HXuW3qsI3Y0zOZFKfZEHcpWiHU/Jxzk629Brsab/mMiHQti9wMP+845RPe3Vg==
 
-json-schema@0.4.0:
-  version "0.4.0"
-  resolved "https://registry.yarnpkg.com/json-schema/-/json-schema-0.4.0.tgz#f7de4cf6efab838ebaeb3236474cbba5a1930ab5"
-  integrity sha512-es94M3nTIfsEPisRafak+HDLfHXnKBhV3vU5eqPcS3flIWqcxJWgXHXiey3YrpaNsanY5ei1VoYEbOzijuq9BA==
-
 json-stable-stringify-without-jsonify@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/json-stable-stringify-without-jsonify/-/json-stable-stringify-without-jsonify-1.0.1.tgz#9db7b59496ad3f3cfef30a75142d2d930ad72651"
   integrity sha512-Bdboy+l7tA3OGW6FjyFHWkP5LuByj1Tk33Ljyq0axyzdk9//JSi2u3fP1QSmd1KNwq6VOKYGlAu87CisVir6Pw==
 
-json-stringify-safe@~5.0.1:
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/json-stringify-safe/-/json-stringify-safe-5.0.1.tgz#1296a2d58fd45f19a0f6ce01d65701e2c735b6eb"
-  integrity sha512-ZClg6AaYvamvYEE82d3Iyd3vSSIjQ+odgjaTzRuO3s7toCdFKczob2i0zCh7JE8kWn17yvAWhUVxvqGwUalsRA==
-
 json5@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/json5/-/json5-1.0.1.tgz#779fb0018604fa854eacbf6252180d83543e3dbe"
@@ -4815,16 +4646,6 @@ jsonparse@^1.2.0:
   resolved "https://registry.yarnpkg.com/jsonparse/-/jsonparse-1.3.1.tgz#3f4dae4a91fac315f71062f8521cc239f1366280"
   integrity sha512-POQXvpdL69+CluYsillJ7SUhKvytYjW9vG/GKpnf+xP8UWgYEM/RaMzHHofbALDiKbbP1W8UEYmgGl39WkPZsg==
 
-jsprim@^1.2.2:
-  version "1.4.2"
-  resolved "https://registry.yarnpkg.com/jsprim/-/jsprim-1.4.2.tgz#712c65533a15c878ba59e9ed5f0e26d5b77c5feb"
-  integrity sha512-P2bSOMAc/ciLz6DzgjVlGJP9+BrJWu5UDGK70C2iweC5QBIeFf0ZXRvGjEj2uYgrY2MkAAhsSWHDWlFtEroZWw==
-  dependencies:
-    assert-plus "1.0.0"
-    extsprintf "1.3.0"
-    json-schema "0.4.0"
-    verror "1.10.0"
-
 jstransformer@1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/jstransformer/-/jstransformer-1.0.0.tgz#ed8bf0921e2f3f1ed4d5c1a44f68709ed24722c3"
@@ -5034,10 +4855,10 @@ matrix-events-sdk@^0.0.1-beta.7:
   resolved "https://registry.yarnpkg.com/matrix-events-sdk/-/matrix-events-sdk-0.0.1-beta.7.tgz#5ffe45eba1f67cc8d7c2377736c728b322524934"
   integrity sha512-9jl4wtWanUFSy2sr2lCjErN/oC8KTAtaeaozJtrgot1JiQcEI4Rda9OLgQ7nLKaqb4Z/QUx/fR3XpDzm5Jy1JA==
 
-matrix-mock-request@^2.1.2:
-  version "2.4.1"
-  resolved "https://registry.yarnpkg.com/matrix-mock-request/-/matrix-mock-request-2.4.1.tgz#a9c7dbb6b466f582ba2ca21f17cf18ceb41c7657"
-  integrity sha512-QMNpKUeHS2RHovSKybUySFTXTJ11EQPkp3bgvEXmNqAc3TYM23gKYqgI288BoBDYwQrK3WJFT0d4bvMiNIS/vA==
+matrix-mock-request@^2.5.0:
+  version "2.5.0"
+  resolved "https://registry.yarnpkg.com/matrix-mock-request/-/matrix-mock-request-2.5.0.tgz#78da2590e82be2e31edcf9814833af5e5f8d2f1a"
+  integrity sha512-7T3gklpW+4rfHsTnp/FDML7aWoBrXhAh8+1ltinQfAh9TDj6y382z/RUMR7i03d1WDzt/ed1UTihqO5GDoOq9Q==
   dependencies:
     expect "^28.1.0"
 
@@ -5095,18 +4916,6 @@ miller-rabin@^4.0.0:
     bn.js "^4.0.0"
     brorand "^1.0.1"
 
-mime-db@1.52.0:
-  version "1.52.0"
-  resolved "https://registry.yarnpkg.com/mime-db/-/mime-db-1.52.0.tgz#bbabcdc02859f4987301c856e3387ce5ec43bf70"
-  integrity sha512-sPU4uV7dYlvtWJxwwxHD0PuihVNiE7TyAbQ5SWxDCB9mUYvOgroQOwYQQOKPJ8CIbE+1ETVlOoK1UC2nU3gYvg==
-
-mime-types@^2.1.12, mime-types@~2.1.19:
-  version "2.1.35"
-  resolved "https://registry.yarnpkg.com/mime-types/-/mime-types-2.1.35.tgz#381a871b62a734450660ae3deee44813f70d959a"
-  integrity sha512-ZDY+bPm5zTTF+YpCrAU9nK0UgICYPT0QtT1NZWFv4s++TNkcgVaT0g6+4R2uI4MjQjzysHB1zxuWL50hzaeXiw==
-  dependencies:
-    mime-db "1.52.0"
-
 mimic-fn@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-2.1.0.tgz#7ed2c2ccccaf84d3ffcb7a69b57711fc2083401b"
@@ -5244,11 +5053,6 @@ npm-run-path@^4.0.1:
   dependencies:
     path-key "^3.0.0"
 
-oauth-sign@~0.9.0:
-  version "0.9.0"
-  resolved "https://registry.yarnpkg.com/oauth-sign/-/oauth-sign-0.9.0.tgz#47a7b016baa68b5fa0ecf3dee08a85c679ac6455"
-  integrity sha512-fexhUFFPTGV8ybAtSIGbV6gOkSv8UtRbDBnAyLQw4QPKkgNlsH2ByPGtMUqdWkos6YCRmAqViwgZrJc/mRDzZQ==
-
 object-assign@^4.0.1, object-assign@^4.1.0, object-assign@^4.1.1:
   version "4.1.1"
   resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"
@@ -5469,11 +5273,6 @@ pbkdf2@^3.0.3:
     safe-buffer "^5.0.1"
     sha.js "^2.4.8"
 
-performance-now@^2.1.0:
-  version "2.1.0"
-  resolved "https://registry.yarnpkg.com/performance-now/-/performance-now-2.1.0.tgz#6309f4e0e5fa913ec1c69307ae364b4b377c9e7b"
-  integrity sha512-7EAHlyLHI56VEIdK57uwHdHKIaAGbnXPiw0yWbarQZOKaKpvUIgW0jWRVLiatnM+XXlSwsanIBH/hzGMJulMow==
-
 picocolors@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/picocolors/-/picocolors-1.0.0.tgz#cb5bdc74ff3f51892236eaf79d68bc44564ab81c"
@@ -5576,11 +5375,6 @@ pseudomap@^1.0.2:
   resolved "https://registry.yarnpkg.com/pseudomap/-/pseudomap-1.0.2.tgz#f052a28da70e618917ef0a8ac34c1ae5a68286b3"
   integrity sha512-b/YwNhb8lk1Zz2+bXXpS/LK9OisiZZ1SNsSLxN1x2OXVEhW2Ckr/7mWE5vrC1ZTiJlD9g19jWszTmJsB+oEpFQ==
 
-psl@^1.1.28:
-  version "1.9.0"
-  resolved "https://registry.yarnpkg.com/psl/-/psl-1.9.0.tgz#d0df2a137f00794565fcaf3b2c00cd09f8d5a5a7"
-  integrity sha512-E/ZsdU4HLs/68gYzgGTkMicWTLPdAftJLfJFlLUAAKZGkStNU72sZjT66SnMDVOfOWY/YAoiD7Jxa9iHvngcag==
-
 public-encrypt@^4.0.0:
   version "4.0.3"
   resolved "https://registry.yarnpkg.com/public-encrypt/-/public-encrypt-4.0.3.tgz#4fcc9d77a07e48ba7527e7cbe0de33d0701331e0"
@@ -5720,11 +5514,6 @@ qs@^6.9.6:
   dependencies:
     side-channel "^1.0.4"
 
-qs@~6.5.2:
-  version "6.5.3"
-  resolved "https://registry.yarnpkg.com/qs/-/qs-6.5.3.tgz#3aeeffc91967ef6e35c0e488ef46fb296ab76aad"
-  integrity sha512-qxXIEh4pCGfHICj1mAJQ2/2XVZkjCDTcEgfoSQxc/fYivUZxTkk7L3bDBJSoNrEzXI17oUO5Dp07ktqE5KzczA==
-
 querystring-es3@~0.2.0:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/querystring-es3/-/querystring-es3-0.2.1.tgz#9ec61f79049875707d69414596fd907a4d711e73"
@@ -5924,32 +5713,6 @@ repeat-string@^1.5.2:
   resolved "https://registry.yarnpkg.com/repeat-string/-/repeat-string-1.6.1.tgz#8dcae470e1c88abc2d600fff4a776286da75e637"
   integrity sha512-PV0dzCYDNfRi1jCDbJzpW7jNNDRuCOG/jI5ctQcGKt/clZD+YcPS3yIlWuTJMmESC8aevCFmWJy5wjAFgNqN6w==
 
-request@^2.88.2:
-  version "2.88.2"
-  resolved "https://registry.yarnpkg.com/request/-/request-2.88.2.tgz#d73c918731cb5a87da047e207234146f664d12b3"
-  integrity sha512-MsvtOrfG9ZcrOwAW+Qi+F6HbD0CWXEh9ou77uOb7FM2WPhwT7smM833PzanhJLsgXjN89Ir6V2PczXNnMpwKhw==
-  dependencies:
-    aws-sign2 "~0.7.0"
-    aws4 "^1.8.0"
-    caseless "~0.12.0"
-    combined-stream "~1.0.6"
-    extend "~3.0.2"
-    forever-agent "~0.6.1"
-    form-data "~2.3.2"
-    har-validator "~5.1.3"
-    http-signature "~1.2.0"
-    is-typedarray "~1.0.0"
-    isstream "~0.1.2"
-    json-stringify-safe "~5.0.1"
-    mime-types "~2.1.19"
-    oauth-sign "~0.9.0"
-    performance-now "^2.1.0"
-    qs "~6.5.2"
-    safe-buffer "^5.1.2"
-    tough-cookie "~2.5.0"
-    tunnel-agent "^0.6.0"
-    uuid "^3.3.2"
-
 require-directory@^2.1.1:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/require-directory/-/require-directory-2.1.1.tgz#8c64ad5fd30dab1c976e2344ffe7f792a6a6df42"
@@ -6051,7 +5814,7 @@ safe-regex-test@^1.0.0:
     get-intrinsic "^1.1.3"
     is-regex "^1.1.4"
 
-safer-buffer@^2.0.2, safer-buffer@^2.1.0, safer-buffer@~2.1.0:
+safer-buffer@^2.1.0:
   version "2.1.2"
   resolved "https://registry.yarnpkg.com/safer-buffer/-/safer-buffer-2.1.2.tgz#44fa161b0187b9549dd84bb91802f9bd8385cd6a"
   integrity sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==
@@ -6189,21 +5952,6 @@ sprintf-js@~1.0.2:
   resolved "https://registry.yarnpkg.com/sprintf-js/-/sprintf-js-1.0.3.tgz#04e6926f662895354f3dd015203633b857297e2c"
   integrity sha512-D9cPgkvLlV3t3IzL0D0YLvGA9Ahk4PcvVwUbN0dSGr1aP0Nrt4AEnTUbuGvquEC0mA64Gqt1fzirlRs5ibXx8g==
 
-sshpk@^1.7.0:
-  version "1.17.0"
-  resolved "https://registry.yarnpkg.com/sshpk/-/sshpk-1.17.0.tgz#578082d92d4fe612b13007496e543fa0fbcbe4c5"
-  integrity sha512-/9HIEs1ZXGhSPE8X6Ccm7Nam1z8KcoCqPdI7ecm1N33EzAetWahvQWVqLZtaZQ+IDKX4IyA2o0gBzqIMkAagHQ==
-  dependencies:
-    asn1 "~0.2.3"
-    assert-plus "^1.0.0"
-    bcrypt-pbkdf "^1.0.0"
-    dashdash "^1.12.0"
-    ecc-jsbn "~0.1.1"
-    getpass "^0.1.1"
-    jsbn "~0.1.0"
-    safer-buffer "^2.0.2"
-    tweetnacl "~0.14.0"
-
 stack-utils@^2.0.3:
   version "2.0.5"
   resolved "https://registry.yarnpkg.com/stack-utils/-/stack-utils-2.0.5.tgz#d25265fca995154659dbbfba3b49254778d2fdd5"
@@ -6506,14 +6254,6 @@ token-stream@0.0.1:
   resolved "https://registry.yarnpkg.com/token-stream/-/token-stream-0.0.1.tgz#ceeefc717a76c4316f126d0b9dbaa55d7e7df01a"
   integrity sha512-nfjOAu/zAWmX9tgwi5NRp7O7zTDUD1miHiB40klUnAh9qnL1iXdgzcz/i5dMaL5jahcBAaSfmNOBBJBLJW8TEg==
 
-tough-cookie@~2.5.0:
-  version "2.5.0"
-  resolved "https://registry.yarnpkg.com/tough-cookie/-/tough-cookie-2.5.0.tgz#cd9fb2a0aa1d5a12b473bd9fb96fa3dcff65ade2"
-  integrity sha512-nlLsUzgm1kfLXSXfRZMc1KLAugd4hqJHDTvc2hDIwS3mZAfMEuMbc03SujMF+GEcpaX/qboeycw6iO8JwVv2+g==
-  dependencies:
-    psl "^1.1.28"
-    punycode "^2.1.1"
-
 tr46@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/tr46/-/tr46-2.1.0.tgz#fa87aa81ca5d5941da8cbf1f9b749dc969a4e240"
@@ -6585,23 +6325,11 @@ tty-browserify@0.0.1:
   resolved "https://registry.yarnpkg.com/tty-browserify/-/tty-browserify-0.0.1.tgz#3f05251ee17904dfd0677546670db9651682b811"
   integrity sha512-C3TaO7K81YvjCgQH9Q1S3R3P3BtN3RIM8n+OvX4il1K1zgE8ZhI0op7kClgkxtutIE8hQrcrHBXvIheqKUUCxw==
 
-tunnel-agent@^0.6.0:
-  version "0.6.0"
-  resolved "https://registry.yarnpkg.com/tunnel-agent/-/tunnel-agent-0.6.0.tgz#27a5dea06b36b04a0a9966774b290868f0fc40fd"
-  integrity sha512-McnNiV1l8RYeY8tBgEpuodCC1mLUdbSN+CYBL7kJsJNInOP8UjDDEwdk6Mw60vdLLrr5NHKZhMAOSrR2NZuQ+w==
-  dependencies:
-    safe-buffer "^5.0.1"
-
 tunnel@^0.0.6:
   version "0.0.6"
   resolved "https://registry.yarnpkg.com/tunnel/-/tunnel-0.0.6.tgz#72f1314b34a5b192db012324df2cc587ca47f92c"
   integrity sha512-1h/Lnq9yajKY2PEbBadPXj3VxsDDu844OnaAo52UVmIzIvwwtBPIuNvkjuzBlTWpfJyUbG3ez0KSBibQkj4ojg==
 
-tweetnacl@^0.14.3, tweetnacl@~0.14.0:
-  version "0.14.5"
-  resolved "https://registry.yarnpkg.com/tweetnacl/-/tweetnacl-0.14.5.tgz#5ae68177f192d4456269d108afa93ff8743f4f64"
-  integrity sha512-KXXFFdAbFXY4geFIwoyNK+f5Z1b7swfXABfL7HXCmoIWMKU3dmS26672A4EeQtDzLKy7SXmfBu51JolvEKwtGA==
-
 type-check@^0.4.0, type-check@~0.4.0:
   version "0.4.0"
   resolved "https://registry.yarnpkg.com/type-check/-/type-check-0.4.0.tgz#07b8203bfa7056c0657050e3ccd2c37730bab8f1"
@@ -6794,11 +6522,6 @@ util@~0.12.0:
     safe-buffer "^5.1.2"
     which-typed-array "^1.1.2"
 
-uuid@^3.3.2:
-  version "3.4.0"
-  resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.4.0.tgz#b23e4358afa8a202fe7a100af1f5f883f02007ee"
-  integrity sha512-HjSDRw6gZE5JMggctHBcjVak08+KEVhSIiDzFnT9S9aegmp85S/bReBVTb4QTFaRNptJ9kuYaNhnbNEOkbKb/A==
-
 uuid@^8.3.2:
   version "8.3.2"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-8.3.2.tgz#80d5b5ced271bb9af6c445f21a1a04c606cefbe2"
@@ -6813,15 +6536,6 @@ v8-to-istanbul@^9.0.0, v8-to-istanbul@^9.0.1:
     "@types/istanbul-lib-coverage" "^2.0.1"
     convert-source-map "^1.6.0"
 
-verror@1.10.0:
-  version "1.10.0"
-  resolved "https://registry.yarnpkg.com/verror/-/verror-1.10.0.tgz#3a105ca17053af55d6e270c1f8288682e18da400"
-  integrity sha512-ZZKSmDAEFOijERBLkmYfJ+vmk3w+7hOLYDNkRCuRuMJGEmqYNCNLyBBFwWKVMhfwaEF3WOd0Zlw86U/WC/+nYw==
-  dependencies:
-    assert-plus "^1.0.0"
-    core-util-is "1.0.2"
-    extsprintf "^1.2.0"
-
 vm-browserify@^1.0.0:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/vm-browserify/-/vm-browserify-1.1.2.tgz#78641c488b8e6ca91a75f511e7a3b32a86e5dda0"
@@ -6885,6 +6599,11 @@ webidl-conversions@^6.1.0:
   resolved "https://registry.yarnpkg.com/webidl-conversions/-/webidl-conversions-6.1.0.tgz#9111b4d7ea80acd40f5270d666621afa78b69514"
   integrity sha512-qBIvFLGiBpLjfwmYAaHPXsn+ho5xZnGvyGvsarywGNc8VyQJUMHJ8OBKGGrPER0okBeMDaan4mNBlgBROxuI8w==
 
+webidl-conversions@^7.0.0:
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/webidl-conversions/-/webidl-conversions-7.0.0.tgz#256b4e1882be7debbf01d05f0aa2039778ea080a"
+  integrity sha512-VwddBukDzu71offAQR975unBIGqfKZpM+8ZX6ySk8nYhVoo5CYaZyzt3YBvYtRtO+aoGlqxPg/B87NGVZ/fu6g==
+
 whatwg-url@^5.0.0:
   version "5.0.0"
   resolved "https://registry.yarnpkg.com/whatwg-url/-/whatwg-url-5.0.0.tgz#966454e8765462e37644d3626f6742ce8b70965d"