diff --git a/src/compile/dom/index.ts b/src/compile/dom/index.ts
index e9e27980bb80..35a6ca17114c 100644
--- a/src/compile/dom/index.ts
+++ b/src/compile/dom/index.ts
@@ -227,7 +227,7 @@ export default function dom(
 			this._fragment.c();
 			this._fragment.${block.hasIntroMethod ? 'i' : 'm'}(this.shadowRoot, null);
 
-			if (options.target) this._mount(options.target, options.anchor);
+			if (options.target) this._mount(options.target, options.anchor, ${options.skipIntroByDefault ? `options.intro` : 'true'});
 		` : deindent`
 			if (options.target) {
 				${compiler.options.hydratable
@@ -240,7 +240,7 @@ export default function dom(
 						${options.dev && `if (options.hydrate) throw new Error("options.hydrate only works if the component was compiled with the \`hydratable: true\` option");`}
 						this._fragment.c();
 					`}
-				this._mount(options.target, options.anchor);
+				this._mount(options.target, options.anchor, ${options.skipIntroByDefault ? `options.intro` : 'true'});
 
 				${(compiler.hasComponents || target.hasComplexBindings || hasInitHooks || target.hasIntroTransitions) && deindent`
 					${compiler.hasComponents && `this._lock = true;`}
diff --git a/src/compile/nodes/Component.ts b/src/compile/nodes/Component.ts
index e25703dd2e04..9b14a294524b 100644
--- a/src/compile/nodes/Component.ts
+++ b/src/compile/nodes/Component.ts
@@ -383,7 +383,7 @@ export default class Component extends Node {
 
 			block.builders.mount.addBlock(deindent`
 				if (${name}) {
-					${name}._mount(${parentNode || '#target'}, ${parentNode ? 'null' : 'anchor'});
+					${name}._mount(${parentNode || '#target'}, ${parentNode ? 'null' : 'anchor'}, ${compiler.options.skipIntroByDefault ? 'false' : 'true'});
 					${this.ref && `#component.refs.${this.ref} = ${name};`}
 				}
 			`);
@@ -405,7 +405,7 @@ export default class Component extends Node {
 						${name}._fragment.c();
 
 						${this.children.map(child => child.remount(name))}
-						${name}._mount(${updateMountNode}, ${anchor});
+						${name}._mount(${updateMountNode}, ${anchor}, ${compiler.options.skipIntroByDefault ? 'false' : 'true'});
 
 						${this.handlers.map(handler => deindent`
 							${name}.on("${handler.name}", ${handler.var});
@@ -464,7 +464,7 @@ export default class Component extends Node {
 			}
 
 			block.builders.mount.addLine(
-				`${name}._mount(${parentNode || '#target'}, ${parentNode ? 'null' : 'anchor'});`
+				`${name}._mount(${parentNode || '#target'}, ${parentNode ? 'null' : 'anchor'}, ${compiler.options.skipIntroByDefault ? 'false' : 'true'});`
 			);
 
 			if (updates.length) {
@@ -483,7 +483,7 @@ export default class Component extends Node {
 	}
 
 	remount(name: string) {
-		return `${this.var}._mount(${name}._slotted.default, null);`;
+		return `${this.var}._mount(${name}._slotted.default, null, ${this.compiler.options.skipIntroByDefault ? 'false' : 'true'});`;
 	}
 
 	ssr() {
diff --git a/src/interfaces.ts b/src/interfaces.ts
index 773a93b37f75..1a5c356404c9 100644
--- a/src/interfaces.ts
+++ b/src/interfaces.ts
@@ -64,6 +64,9 @@ export interface CompileOptions {
 
 	onerror?: (error: Error) => void;
 	onwarn?: (warning: Warning) => void;
+
+	// to remove in v3
+	skipIntroByDefault?: boolean;
 }
 
 export interface GenerateOptions {
diff --git a/src/shared/index.js b/src/shared/index.js
index cf82282ad809..e1d7fda5e9f8 100644
--- a/src/shared/index.js
+++ b/src/shared/index.js
@@ -128,8 +128,8 @@ export function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-export function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+export function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 export var PENDING = {};
diff --git a/test/cli/samples/basic/expected/Main.js b/test/cli/samples/basic/expected/Main.js
index dce010fb4c4c..b4b737bb766d 100644
--- a/test/cli/samples/basic/expected/Main.js
+++ b/test/cli/samples/basic/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/custom-element/expected/Main.js b/test/cli/samples/custom-element/expected/Main.js
index d1b96c98992b..6fcf0aa394db 100644
--- a/test/cli/samples/custom-element/expected/Main.js
+++ b/test/cli/samples/custom-element/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -37,7 +37,7 @@ class Main extends HTMLElement {
 		this._fragment.c();
 		this._fragment.m(this.shadowRoot, null);
 
-		if (options.target) this._mount(options.target, options.anchor);
+		if (options.target) this._mount(options.target, options.anchor, true);
 	}
 
 	static get observedAttributes() {
@@ -170,8 +170,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dev/expected/Main.js b/test/cli/samples/dev/expected/Main.js
index a2da6346b646..9c8394917ce6 100644
--- a/test/cli/samples/dev/expected/Main.js
+++ b/test/cli/samples/dev/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -34,7 +34,7 @@ function Main(options) {
 	if (options.target) {
 		if (options.hydrate) throw new Error("options.hydrate only works if the component was compiled with the `hydratable: true` option");
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -153,8 +153,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir-sourcemap/expected/Main.js b/test/cli/samples/dir-sourcemap/expected/Main.js
index b4a005c0ac5f..ccedf5a18ade 100644
--- a/test/cli/samples/dir-sourcemap/expected/Main.js
+++ b/test/cli/samples/dir-sourcemap/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 import Widget from './Widget.html';
 
 
@@ -15,7 +15,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			widget._mount(target, anchor);
+			widget._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -40,7 +40,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
@@ -156,8 +156,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir-sourcemap/expected/Widget.js b/test/cli/samples/dir-sourcemap/expected/Widget.js
index 28223fdd1c0e..702f6ee812a1 100644
--- a/test/cli/samples/dir-sourcemap/expected/Widget.js
+++ b/test/cli/samples/dir-sourcemap/expected/Widget.js
@@ -1,4 +1,4 @@
-/* src/Widget.html generated by Svelte v2.4.4 */
+/* src/Widget.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Widget(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir-subdir/expected/Main.js b/test/cli/samples/dir-subdir/expected/Main.js
index 1a595e80dd4f..c43c92222022 100644
--- a/test/cli/samples/dir-subdir/expected/Main.js
+++ b/test/cli/samples/dir-subdir/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 import Widget from './widget/Widget.html';
 
 
@@ -15,7 +15,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			widget._mount(target, anchor);
+			widget._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -40,7 +40,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
@@ -156,8 +156,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir-subdir/expected/widget/Widget.js b/test/cli/samples/dir-subdir/expected/widget/Widget.js
index 7ab7e73f96c1..df8b286b2926 100644
--- a/test/cli/samples/dir-subdir/expected/widget/Widget.js
+++ b/test/cli/samples/dir-subdir/expected/widget/Widget.js
@@ -1,4 +1,4 @@
-/* src/widget/Widget.html generated by Svelte v2.4.4 */
+/* src/widget/Widget.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Widget(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir/expected/Main.js b/test/cli/samples/dir/expected/Main.js
index 43ff753ecad4..501d7d8e9f7a 100644
--- a/test/cli/samples/dir/expected/Main.js
+++ b/test/cli/samples/dir/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 import Widget from './Widget.html';
 
 
@@ -15,7 +15,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			widget._mount(target, anchor);
+			widget._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -40,7 +40,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
@@ -156,8 +156,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/dir/expected/Widget.js b/test/cli/samples/dir/expected/Widget.js
index 9c62194627df..ad7f1ce7edb2 100644
--- a/test/cli/samples/dir/expected/Widget.js
+++ b/test/cli/samples/dir/expected/Widget.js
@@ -1,4 +1,4 @@
-/* src/Widget.html generated by Svelte v2.4.4 */
+/* src/Widget.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Widget(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/globals/expected/Main.js b/test/cli/samples/globals/expected/Main.js
index 968eb228fec7..72daf778fbc6 100644
--- a/test/cli/samples/globals/expected/Main.js
+++ b/test/cli/samples/globals/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 var Main = (function(answer) { "use strict";
 	answer = (answer && answer.__esModule) ? answer["default"] : answer;
 
@@ -46,7 +46,7 @@ var Main = (function(answer) { "use strict";
 
 		if (options.target) {
 			this._fragment.c();
-			this._mount(options.target, options.anchor);
+			this._mount(options.target, options.anchor, true);
 		}
 	}
 
@@ -170,8 +170,8 @@ var Main = (function(answer) { "use strict";
 		}
 	}
 
-	function _mount(target, anchor) {
-		this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+	function _mount(target, anchor, intro) {
+		this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 	}
 
 	function _differs(a, b) {
diff --git a/test/cli/samples/sourcemap-inline/expected/Main.js b/test/cli/samples/sourcemap-inline/expected/Main.js
index 3da16e1a57e4..b357420353de 100644
--- a/test/cli/samples/sourcemap-inline/expected/Main.js
+++ b/test/cli/samples/sourcemap-inline/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/sourcemap/expected/Main.js b/test/cli/samples/sourcemap/expected/Main.js
index b44a4b2f2714..14c1518dd09b 100644
--- a/test/cli/samples/sourcemap/expected/Main.js
+++ b/test/cli/samples/sourcemap/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var p;
@@ -31,7 +31,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -149,8 +149,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/cli/samples/store/expected/Main.js b/test/cli/samples/store/expected/Main.js
index 320a159497ae..45ea6ea81451 100644
--- a/test/cli/samples/store/expected/Main.js
+++ b/test/cli/samples/store/expected/Main.js
@@ -1,4 +1,4 @@
-/* src/Main.html generated by Svelte v2.4.4 */
+/* src/Main.html generated by Svelte v2.5.1 */
 
 function create_main_fragment(component, ctx) {
 	var h1, text, text_1;
@@ -41,7 +41,7 @@ function Main(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
@@ -169,8 +169,8 @@ function _set(newState) {
 	}
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 function _differs(a, b) {
diff --git a/test/js/samples/action/expected-bundle.js b/test/js/samples/action/expected-bundle.js
index 49e0372582f3..8828faba1393 100644
--- a/test/js/samples/action/expected-bundle.js
+++ b/test/js/samples/action/expected-bundle.js
@@ -111,8 +111,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -179,7 +179,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/action/expected.js b/test/js/samples/action/expected.js
index f92f3723fe76..dab9d0d9db57 100644
--- a/test/js/samples/action/expected.js
+++ b/test/js/samples/action/expected.js
@@ -52,7 +52,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/bind-width-height/expected-bundle.js b/test/js/samples/bind-width-height/expected-bundle.js
index 371f3d2843c5..11a932ee3f6f 100644
--- a/test/js/samples/bind-width-height/expected-bundle.js
+++ b/test/js/samples/bind-width-height/expected-bundle.js
@@ -143,8 +143,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -205,7 +205,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._beforecreate);
 	}
diff --git a/test/js/samples/bind-width-height/expected.js b/test/js/samples/bind-width-height/expected.js
index 8d9b432ef0ea..12eb1e8c37f0 100644
--- a/test/js/samples/bind-width-height/expected.js
+++ b/test/js/samples/bind-width-height/expected.js
@@ -45,7 +45,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._beforecreate);
 	}
diff --git a/test/js/samples/collapses-text-around-comments/expected-bundle.js b/test/js/samples/collapses-text-around-comments/expected-bundle.js
index 302c1c3aaf4d..a8a0b6f76ba9 100644
--- a/test/js/samples/collapses-text-around-comments/expected-bundle.js
+++ b/test/js/samples/collapses-text-around-comments/expected-bundle.js
@@ -119,8 +119,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -186,7 +186,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/collapses-text-around-comments/expected.js b/test/js/samples/collapses-text-around-comments/expected.js
index 75d00262c0d8..78e957933fb5 100644
--- a/test/js/samples/collapses-text-around-comments/expected.js
+++ b/test/js/samples/collapses-text-around-comments/expected.js
@@ -51,7 +51,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/component-static-array/expected-bundle.js b/test/js/samples/component-static-array/expected-bundle.js
index 871a50c7cc5d..24e739c61af4 100644
--- a/test/js/samples/component-static-array/expected-bundle.js
+++ b/test/js/samples/component-static-array/expected-bundle.js
@@ -99,8 +99,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -133,7 +133,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -158,7 +158,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static-array/expected.js b/test/js/samples/component-static-array/expected.js
index f07b2d8ed366..667fa7f4869f 100644
--- a/test/js/samples/component-static-array/expected.js
+++ b/test/js/samples/component-static-array/expected.js
@@ -17,7 +17,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -42,7 +42,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static-immutable/expected-bundle.js b/test/js/samples/component-static-immutable/expected-bundle.js
index 93a558f4acef..f272d7e11a65 100644
--- a/test/js/samples/component-static-immutable/expected-bundle.js
+++ b/test/js/samples/component-static-immutable/expected-bundle.js
@@ -103,8 +103,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -137,7 +137,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -162,7 +162,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static-immutable/expected.js b/test/js/samples/component-static-immutable/expected.js
index c18720c54ac8..877cbd5eda18 100644
--- a/test/js/samples/component-static-immutable/expected.js
+++ b/test/js/samples/component-static-immutable/expected.js
@@ -17,7 +17,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -42,7 +42,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static-immutable2/expected-bundle.js b/test/js/samples/component-static-immutable2/expected-bundle.js
index 93a558f4acef..f272d7e11a65 100644
--- a/test/js/samples/component-static-immutable2/expected-bundle.js
+++ b/test/js/samples/component-static-immutable2/expected-bundle.js
@@ -103,8 +103,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -137,7 +137,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -162,7 +162,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static-immutable2/expected.js b/test/js/samples/component-static-immutable2/expected.js
index c18720c54ac8..877cbd5eda18 100644
--- a/test/js/samples/component-static-immutable2/expected.js
+++ b/test/js/samples/component-static-immutable2/expected.js
@@ -17,7 +17,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -42,7 +42,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static/expected-bundle.js b/test/js/samples/component-static/expected-bundle.js
index bf7121708aba..04bd0982b57c 100644
--- a/test/js/samples/component-static/expected-bundle.js
+++ b/test/js/samples/component-static/expected-bundle.js
@@ -99,8 +99,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -133,7 +133,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -158,7 +158,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/component-static/expected.js b/test/js/samples/component-static/expected.js
index 206232418244..631d2e781459 100644
--- a/test/js/samples/component-static/expected.js
+++ b/test/js/samples/component-static/expected.js
@@ -17,7 +17,7 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			nested._mount(target, anchor);
+			nested._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -42,7 +42,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/computed-collapsed-if/expected-bundle.js b/test/js/samples/computed-collapsed-if/expected-bundle.js
index 1a44c576c579..c40522136571 100644
--- a/test/js/samples/computed-collapsed-if/expected-bundle.js
+++ b/test/js/samples/computed-collapsed-if/expected-bundle.js
@@ -99,8 +99,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -147,7 +147,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/computed-collapsed-if/expected.js b/test/js/samples/computed-collapsed-if/expected.js
index 8ca8d597ee54..05f6ae2bff60 100644
--- a/test/js/samples/computed-collapsed-if/expected.js
+++ b/test/js/samples/computed-collapsed-if/expected.js
@@ -31,7 +31,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/css-media-query/expected-bundle.js b/test/js/samples/css-media-query/expected-bundle.js
index 446ff232022a..0c864a18ec10 100644
--- a/test/js/samples/css-media-query/expected-bundle.js
+++ b/test/js/samples/css-media-query/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -173,7 +173,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/css-media-query/expected.js b/test/js/samples/css-media-query/expected.js
index b307708cb322..9b8c88b3ef6e 100644
--- a/test/js/samples/css-media-query/expected.js
+++ b/test/js/samples/css-media-query/expected.js
@@ -41,7 +41,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js b/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
index 86bef96e53a9..8277f96654ae 100644
--- a/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
+++ b/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
@@ -111,8 +111,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -167,7 +167,7 @@ class SvelteComponent extends HTMLElement {
 		this._fragment.c();
 		this._fragment.m(this.shadowRoot, null);
 
-		if (options.target) this._mount(options.target, options.anchor);
+		if (options.target) this._mount(options.target, options.anchor, true);
 	}
 
 	static get observedAttributes() {
diff --git a/test/js/samples/css-shadow-dom-keyframes/expected.js b/test/js/samples/css-shadow-dom-keyframes/expected.js
index e86d8a3cb309..085cccb8d705 100644
--- a/test/js/samples/css-shadow-dom-keyframes/expected.js
+++ b/test/js/samples/css-shadow-dom-keyframes/expected.js
@@ -39,7 +39,7 @@ class SvelteComponent extends HTMLElement {
 		this._fragment.c();
 		this._fragment.m(this.shadowRoot, null);
 
-		if (options.target) this._mount(options.target, options.anchor);
+		if (options.target) this._mount(options.target, options.anchor, true);
 	}
 
 	static get observedAttributes() {
diff --git a/test/js/samples/deconflict-builtins/expected-bundle.js b/test/js/samples/deconflict-builtins/expected-bundle.js
index effd1571f618..4767d5ccecb1 100644
--- a/test/js/samples/deconflict-builtins/expected-bundle.js
+++ b/test/js/samples/deconflict-builtins/expected-bundle.js
@@ -129,8 +129,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -253,7 +253,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/deconflict-builtins/expected.js b/test/js/samples/deconflict-builtins/expected.js
index 8ae4b5dc3ea8..50a8aa2b43ca 100644
--- a/test/js/samples/deconflict-builtins/expected.js
+++ b/test/js/samples/deconflict-builtins/expected.js
@@ -107,7 +107,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/deconflict-globals/expected-bundle.js b/test/js/samples/deconflict-globals/expected-bundle.js
index 06e30f87bcaa..9983368542ff 100644
--- a/test/js/samples/deconflict-globals/expected-bundle.js
+++ b/test/js/samples/deconflict-globals/expected-bundle.js
@@ -104,8 +104,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -161,7 +161,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._oncreate);
 	}
diff --git a/test/js/samples/deconflict-globals/expected.js b/test/js/samples/deconflict-globals/expected.js
index afac48dfbd42..f19fe3af9cb9 100644
--- a/test/js/samples/deconflict-globals/expected.js
+++ b/test/js/samples/deconflict-globals/expected.js
@@ -41,7 +41,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._oncreate);
 	}
diff --git a/test/js/samples/dev-warning-missing-data-computed/expected-bundle.js b/test/js/samples/dev-warning-missing-data-computed/expected-bundle.js
index bb93b058410a..0d93b49f8f36 100644
--- a/test/js/samples/dev-warning-missing-data-computed/expected-bundle.js
+++ b/test/js/samples/dev-warning-missing-data-computed/expected-bundle.js
@@ -137,8 +137,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var protoDev = {
@@ -208,7 +208,7 @@ function SvelteComponent(options) {
 	if (options.target) {
 		if (options.hydrate) throw new Error("options.hydrate only works if the component was compiled with the `hydratable: true` option");
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/dev-warning-missing-data-computed/expected.js b/test/js/samples/dev-warning-missing-data-computed/expected.js
index 5efb1f0a5ec4..7ef01fe7961f 100644
--- a/test/js/samples/dev-warning-missing-data-computed/expected.js
+++ b/test/js/samples/dev-warning-missing-data-computed/expected.js
@@ -54,7 +54,7 @@ function SvelteComponent(options) {
 	if (options.target) {
 		if (options.hydrate) throw new Error("options.hydrate only works if the component was compiled with the `hydratable: true` option");
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/do-use-dataset/expected-bundle.js b/test/js/samples/do-use-dataset/expected-bundle.js
index e30355de2502..056964765dc3 100644
--- a/test/js/samples/do-use-dataset/expected-bundle.js
+++ b/test/js/samples/do-use-dataset/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -175,7 +175,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/do-use-dataset/expected.js b/test/js/samples/do-use-dataset/expected.js
index a57edb8483b2..4d3773a37a25 100644
--- a/test/js/samples/do-use-dataset/expected.js
+++ b/test/js/samples/do-use-dataset/expected.js
@@ -43,7 +43,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js b/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
index 3cbc5ca530f4..dd7e1117257a 100644
--- a/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
+++ b/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
@@ -119,8 +119,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -179,7 +179,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/dont-use-dataset-in-legacy/expected.js b/test/js/samples/dont-use-dataset-in-legacy/expected.js
index 1475687e2d47..266cc25e96b6 100644
--- a/test/js/samples/dont-use-dataset-in-legacy/expected.js
+++ b/test/js/samples/dont-use-dataset-in-legacy/expected.js
@@ -43,7 +43,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js b/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
index 80e1f6036685..810683ae14fe 100644
--- a/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
+++ b/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
@@ -119,8 +119,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -177,7 +177,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/dont-use-dataset-in-svg/expected.js b/test/js/samples/dont-use-dataset-in-svg/expected.js
index 42bc11876efc..359de3a16cf1 100644
--- a/test/js/samples/dont-use-dataset-in-svg/expected.js
+++ b/test/js/samples/dont-use-dataset-in-svg/expected.js
@@ -41,7 +41,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/each-block-changed-check/expected-bundle.js b/test/js/samples/each-block-changed-check/expected-bundle.js
index 2c2c8838da52..fb82c1ef93c4 100644
--- a/test/js/samples/each-block-changed-check/expected-bundle.js
+++ b/test/js/samples/each-block-changed-check/expected-bundle.js
@@ -131,8 +131,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -294,7 +294,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/each-block-changed-check/expected.js b/test/js/samples/each-block-changed-check/expected.js
index 609556bae0f2..82c588c9390f 100644
--- a/test/js/samples/each-block-changed-check/expected.js
+++ b/test/js/samples/each-block-changed-check/expected.js
@@ -146,7 +146,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/event-handlers-custom/expected-bundle.js b/test/js/samples/event-handlers-custom/expected-bundle.js
index 10715bd84c33..661c52fcf4f1 100644
--- a/test/js/samples/event-handlers-custom/expected-bundle.js
+++ b/test/js/samples/event-handlers-custom/expected-bundle.js
@@ -111,8 +111,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -177,7 +177,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/event-handlers-custom/expected.js b/test/js/samples/event-handlers-custom/expected.js
index 86741c470c06..3e8b5b528b67 100644
--- a/test/js/samples/event-handlers-custom/expected.js
+++ b/test/js/samples/event-handlers-custom/expected.js
@@ -50,7 +50,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/head-no-whitespace/expected-bundle.js b/test/js/samples/head-no-whitespace/expected-bundle.js
index 539ea3e5a4df..a39755bdd5da 100644
--- a/test/js/samples/head-no-whitespace/expected-bundle.js
+++ b/test/js/samples/head-no-whitespace/expected-bundle.js
@@ -111,8 +111,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -164,7 +164,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/head-no-whitespace/expected.js b/test/js/samples/head-no-whitespace/expected.js
index 58b3f0e31185..3be9e7938971 100644
--- a/test/js/samples/head-no-whitespace/expected.js
+++ b/test/js/samples/head-no-whitespace/expected.js
@@ -36,7 +36,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/if-block-no-update/expected-bundle.js b/test/js/samples/if-block-no-update/expected-bundle.js
index d54a62c22783..54712a53957d 100644
--- a/test/js/samples/if-block-no-update/expected-bundle.js
+++ b/test/js/samples/if-block-no-update/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -225,7 +225,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/if-block-no-update/expected.js b/test/js/samples/if-block-no-update/expected.js
index 6bed171850a8..f6a3f03c03b2 100644
--- a/test/js/samples/if-block-no-update/expected.js
+++ b/test/js/samples/if-block-no-update/expected.js
@@ -93,7 +93,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/if-block-simple/expected-bundle.js b/test/js/samples/if-block-simple/expected-bundle.js
index 9a067201fbf8..1d1d2088ed0d 100644
--- a/test/js/samples/if-block-simple/expected-bundle.js
+++ b/test/js/samples/if-block-simple/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -201,7 +201,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/if-block-simple/expected.js b/test/js/samples/if-block-simple/expected.js
index 98458d918fff..d35299a94dd5 100644
--- a/test/js/samples/if-block-simple/expected.js
+++ b/test/js/samples/if-block-simple/expected.js
@@ -69,7 +69,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized-multiple/expected-bundle.js b/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
index 13da6e5fc0aa..cad82c33ca6b 100644
--- a/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -173,7 +173,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized-multiple/expected.js b/test/js/samples/inline-style-optimized-multiple/expected.js
index 742da2b3d9ec..0be17478ef70 100644
--- a/test/js/samples/inline-style-optimized-multiple/expected.js
+++ b/test/js/samples/inline-style-optimized-multiple/expected.js
@@ -41,7 +41,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized-url/expected-bundle.js b/test/js/samples/inline-style-optimized-url/expected-bundle.js
index f27fd1f154f3..250878e4d781 100644
--- a/test/js/samples/inline-style-optimized-url/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized-url/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -168,7 +168,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized-url/expected.js b/test/js/samples/inline-style-optimized-url/expected.js
index 2eb51e081805..d31dec9c815c 100644
--- a/test/js/samples/inline-style-optimized-url/expected.js
+++ b/test/js/samples/inline-style-optimized-url/expected.js
@@ -36,7 +36,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized/expected-bundle.js b/test/js/samples/inline-style-optimized/expected-bundle.js
index 1df7465c86f8..ec403776a751 100644
--- a/test/js/samples/inline-style-optimized/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -168,7 +168,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-optimized/expected.js b/test/js/samples/inline-style-optimized/expected.js
index 9c55bc6e8451..a4f7da55459d 100644
--- a/test/js/samples/inline-style-optimized/expected.js
+++ b/test/js/samples/inline-style-optimized/expected.js
@@ -36,7 +36,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-unoptimized/expected-bundle.js b/test/js/samples/inline-style-unoptimized/expected-bundle.js
index ed8e4fd01cf6..cba448597908 100644
--- a/test/js/samples/inline-style-unoptimized/expected-bundle.js
+++ b/test/js/samples/inline-style-unoptimized/expected-bundle.js
@@ -115,8 +115,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -179,7 +179,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/inline-style-unoptimized/expected.js b/test/js/samples/inline-style-unoptimized/expected.js
index 41ffd501e014..b0a1f77b667c 100644
--- a/test/js/samples/inline-style-unoptimized/expected.js
+++ b/test/js/samples/inline-style-unoptimized/expected.js
@@ -47,7 +47,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/input-range/expected-bundle.js b/test/js/samples/input-range/expected-bundle.js
index 048c9e088ff1..3df312e184f8 100644
--- a/test/js/samples/input-range/expected-bundle.js
+++ b/test/js/samples/input-range/expected-bundle.js
@@ -127,8 +127,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -189,7 +189,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/input-range/expected.js b/test/js/samples/input-range/expected.js
index 0899036bac8c..4468c4c92d58 100644
--- a/test/js/samples/input-range/expected.js
+++ b/test/js/samples/input-range/expected.js
@@ -45,7 +45,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/input-without-blowback-guard/expected-bundle.js b/test/js/samples/input-without-blowback-guard/expected-bundle.js
index 67915bc81b61..265fc37de50b 100644
--- a/test/js/samples/input-without-blowback-guard/expected-bundle.js
+++ b/test/js/samples/input-without-blowback-guard/expected-bundle.js
@@ -123,8 +123,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -183,7 +183,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/input-without-blowback-guard/expected.js b/test/js/samples/input-without-blowback-guard/expected.js
index 635987f16b4f..9b74212e6835 100644
--- a/test/js/samples/input-without-blowback-guard/expected.js
+++ b/test/js/samples/input-without-blowback-guard/expected.js
@@ -43,7 +43,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/legacy-input-type/expected-bundle.js b/test/js/samples/legacy-input-type/expected-bundle.js
index 9f806ed42a0c..69238bd3a00c 100644
--- a/test/js/samples/legacy-input-type/expected-bundle.js
+++ b/test/js/samples/legacy-input-type/expected-bundle.js
@@ -117,8 +117,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -166,7 +166,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/legacy-input-type/expected.js b/test/js/samples/legacy-input-type/expected.js
index 2e1c279b2080..bbdf477d4963 100644
--- a/test/js/samples/legacy-input-type/expected.js
+++ b/test/js/samples/legacy-input-type/expected.js
@@ -32,7 +32,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/media-bindings/expected-bundle.js b/test/js/samples/media-bindings/expected-bundle.js
index fbb235a80d16..0d6da357e1d0 100644
--- a/test/js/samples/media-bindings/expected-bundle.js
+++ b/test/js/samples/media-bindings/expected-bundle.js
@@ -127,8 +127,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -237,7 +237,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._beforecreate);
 	}
diff --git a/test/js/samples/media-bindings/expected.js b/test/js/samples/media-bindings/expected.js
index f2400877e23b..049662796874 100644
--- a/test/js/samples/media-bindings/expected.js
+++ b/test/js/samples/media-bindings/expected.js
@@ -93,7 +93,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		callAll(this._beforecreate);
 	}
diff --git a/test/js/samples/non-imported-component/expected-bundle.js b/test/js/samples/non-imported-component/expected-bundle.js
index bfab868082d2..04347d853a32 100644
--- a/test/js/samples/non-imported-component/expected-bundle.js
+++ b/test/js/samples/non-imported-component/expected-bundle.js
@@ -113,8 +113,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -152,9 +152,9 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			imported._mount(target, anchor);
+			imported._mount(target, anchor, true);
 			insertNode(text, target, anchor);
-			nonimported._mount(target, anchor);
+			nonimported._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -184,7 +184,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/non-imported-component/expected.js b/test/js/samples/non-imported-component/expected.js
index c070fa76d442..cb22b9704037 100644
--- a/test/js/samples/non-imported-component/expected.js
+++ b/test/js/samples/non-imported-component/expected.js
@@ -23,9 +23,9 @@ function create_main_fragment(component, ctx) {
 		},
 
 		m(target, anchor) {
-			imported._mount(target, anchor);
+			imported._mount(target, anchor, true);
 			insertNode(text, target, anchor);
-			nonimported._mount(target, anchor);
+			nonimported._mount(target, anchor, true);
 		},
 
 		p: noop,
@@ -55,7 +55,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 
 		this._lock = true;
 		callAll(this._beforecreate);
diff --git a/test/js/samples/setup-method/expected-bundle.js b/test/js/samples/setup-method/expected-bundle.js
index 30d69d6180ce..d2801647e5e9 100644
--- a/test/js/samples/setup-method/expected-bundle.js
+++ b/test/js/samples/setup-method/expected-bundle.js
@@ -99,8 +99,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -154,7 +154,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/setup-method/expected.js b/test/js/samples/setup-method/expected.js
index 855e7635b0a3..0dc82648fb11 100644
--- a/test/js/samples/setup-method/expected.js
+++ b/test/js/samples/setup-method/expected.js
@@ -38,7 +38,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/svg-title/expected-bundle.js b/test/js/samples/svg-title/expected-bundle.js
index faf86f14cbfd..28f5220935c0 100644
--- a/test/js/samples/svg-title/expected-bundle.js
+++ b/test/js/samples/svg-title/expected-bundle.js
@@ -119,8 +119,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -171,7 +171,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/svg-title/expected.js b/test/js/samples/svg-title/expected.js
index 96a1ea09d1e1..b5f7caf1983a 100644
--- a/test/js/samples/svg-title/expected.js
+++ b/test/js/samples/svg-title/expected.js
@@ -35,7 +35,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/title/expected-bundle.js b/test/js/samples/title/expected-bundle.js
index 1c4fd5e84fad..bd918afa0da1 100644
--- a/test/js/samples/title/expected-bundle.js
+++ b/test/js/samples/title/expected-bundle.js
@@ -99,8 +99,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -145,7 +145,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/title/expected.js b/test/js/samples/title/expected.js
index f5aa312569f6..6b9d49466d1c 100644
--- a/test/js/samples/title/expected.js
+++ b/test/js/samples/title/expected.js
@@ -29,7 +29,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/use-elements-as-anchors/expected-bundle.js b/test/js/samples/use-elements-as-anchors/expected-bundle.js
index 3a3879b91e83..66a472d56d52 100644
--- a/test/js/samples/use-elements-as-anchors/expected-bundle.js
+++ b/test/js/samples/use-elements-as-anchors/expected-bundle.js
@@ -123,8 +123,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -389,7 +389,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/use-elements-as-anchors/expected.js b/test/js/samples/use-elements-as-anchors/expected.js
index 9e33cb6e03e9..20cf05be0c02 100644
--- a/test/js/samples/use-elements-as-anchors/expected.js
+++ b/test/js/samples/use-elements-as-anchors/expected.js
@@ -249,7 +249,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/window-binding-scroll/expected-bundle.js b/test/js/samples/window-binding-scroll/expected-bundle.js
index a26fb90ce58c..5b7e8ad96c51 100644
--- a/test/js/samples/window-binding-scroll/expected-bundle.js
+++ b/test/js/samples/window-binding-scroll/expected-bundle.js
@@ -119,8 +119,8 @@ function callAll(fns) {
 	while (fns && fns.length) fns.shift()();
 }
 
-function _mount(target, anchor) {
-	this._fragment[this._fragment.i ? 'i' : 'm'](target, anchor || null);
+function _mount(target, anchor, intro) {
+	this._fragment[intro && this._fragment.i ? 'i' : 'm'](target, anchor || null);
 }
 
 var proto = {
@@ -198,7 +198,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/js/samples/window-binding-scroll/expected.js b/test/js/samples/window-binding-scroll/expected.js
index ce8a8213b64a..eb0904d9c72a 100644
--- a/test/js/samples/window-binding-scroll/expected.js
+++ b/test/js/samples/window-binding-scroll/expected.js
@@ -62,7 +62,7 @@ function SvelteComponent(options) {
 
 	if (options.target) {
 		this._fragment.c();
-		this._mount(options.target, options.anchor);
+		this._mount(options.target, options.anchor, true);
 	}
 }
 
diff --git a/test/runtime/index.js b/test/runtime/index.js
index 199a9a0c9ba0..1ae37afd612b 100644
--- a/test/runtime/index.js
+++ b/test/runtime/index.js
@@ -72,6 +72,7 @@ describe("runtime", () => {
 			compileOptions.dev = config.dev;
 			compileOptions.store = !!config.store;
 			compileOptions.immutable = config.immutable;
+			compileOptions.skipIntroByDefault = config.skipIntroByDefault;
 
 			Object.keys(require.cache)
 				.filter(x => x.endsWith(".html"))
@@ -134,7 +135,8 @@ describe("runtime", () => {
 						target,
 						hydrate,
 						data: config.data,
-						store: (config.store !== true && config.store)
+						store: (config.store !== true && config.store),
+						intro: config.intro
 					}, config.options || {});
 
 					const component = new SvelteComponent(options);
diff --git a/test/runtime/samples/transition-js-initial/_config.js b/test/runtime/samples/transition-js-initial/_config.js
index f6501ed9202b..752780d6f0b4 100644
--- a/test/runtime/samples/transition-js-initial/_config.js
+++ b/test/runtime/samples/transition-js-initial/_config.js
@@ -1,11 +1,9 @@
 export default {
-	test ( assert, component, target, window, raf ) {
-		const div = target.querySelector( 'div' );
-		assert.equal( div.foo, 0 );
+	test(assert, component, target, window, raf) {
+		const div = target.querySelector('div');
+		assert.equal(div.foo, 0);
 
 		raf.tick(50);
-		assert.equal( div.foo, 0.5 );
-
-		component.destroy();
+		assert.equal(div.foo, 0.5);
 	}
-};
\ No newline at end of file
+};
diff --git a/test/runtime/samples/transition-js-initial/main.html b/test/runtime/samples/transition-js-initial/main.html
index 13ffdc40a8dc..16ced20bc3be 100644
--- a/test/runtime/samples/transition-js-initial/main.html
+++ b/test/runtime/samples/transition-js-initial/main.html
@@ -3,7 +3,7 @@
 <script>
 	export default {
 		transitions: {
-			foo: function ( node, params ) {
+			foo(node, params) {
 				return {
 					duration: 100,
 					tick: t => {
diff --git a/test/runtime/samples/transition-js-intro-enabled-by-option/_config.js b/test/runtime/samples/transition-js-intro-enabled-by-option/_config.js
new file mode 100644
index 000000000000..f3124450dc87
--- /dev/null
+++ b/test/runtime/samples/transition-js-intro-enabled-by-option/_config.js
@@ -0,0 +1,12 @@
+export default {
+	skipIntroByDefault: true,
+	intro: true,
+
+	test(assert, component, target, window, raf) {
+		const div = target.querySelector('div');
+		assert.equal(div.foo, 0);
+
+		raf.tick(50);
+		assert.equal(div.foo, 0.5);
+	},
+};
diff --git a/test/runtime/samples/transition-js-intro-enabled-by-option/main.html b/test/runtime/samples/transition-js-intro-enabled-by-option/main.html
new file mode 100644
index 000000000000..16ced20bc3be
--- /dev/null
+++ b/test/runtime/samples/transition-js-intro-enabled-by-option/main.html
@@ -0,0 +1,16 @@
+<div transition:foo></div>
+
+<script>
+	export default {
+		transitions: {
+			foo(node, params) {
+				return {
+					duration: 100,
+					tick: t => {
+						node.foo = t;
+					}
+				};
+			}
+		}
+	};
+</script>
\ No newline at end of file
diff --git a/test/runtime/samples/transition-js-intro-skipped-by-default/_config.js b/test/runtime/samples/transition-js-intro-skipped-by-default/_config.js
new file mode 100644
index 000000000000..9e63e6c8f731
--- /dev/null
+++ b/test/runtime/samples/transition-js-intro-skipped-by-default/_config.js
@@ -0,0 +1,11 @@
+export default {
+	skipIntroByDefault: true,
+
+	test(assert, component, target, window, raf) {
+		const div = target.querySelector('div');
+		assert.equal(div.foo, undefined);
+
+		raf.tick(50);
+		assert.equal(div.foo, undefined);
+	},
+};
diff --git a/test/runtime/samples/transition-js-intro-skipped-by-default/main.html b/test/runtime/samples/transition-js-intro-skipped-by-default/main.html
new file mode 100644
index 000000000000..16ced20bc3be
--- /dev/null
+++ b/test/runtime/samples/transition-js-intro-skipped-by-default/main.html
@@ -0,0 +1,16 @@
+<div transition:foo></div>
+
+<script>
+	export default {
+		transitions: {
+			foo(node, params) {
+				return {
+					duration: 100,
+					tick: t => {
+						node.foo = t;
+					}
+				};
+			}
+		}
+	};
+</script>
\ No newline at end of file