diff --git a/ci/licenses_golden/licenses_flutter b/ci/licenses_golden/licenses_flutter
index ea0738c72c1b3..77ad3e05aa1a6 100644
--- a/ci/licenses_golden/licenses_flutter
+++ b/ci/licenses_golden/licenses_flutter
@@ -3277,6 +3277,7 @@ FILE: ../../../flutter/shell/platform/windows/windows_proc_table.cc
 FILE: ../../../flutter/shell/platform/windows/windows_proc_table.h
 FILE: ../../../flutter/shell/platform/windows/windows_registry.cc
 FILE: ../../../flutter/shell/platform/windows/windows_registry.h
+FILE: ../../../flutter/shell/platform/windows/windowsx_shim.h
 FILE: ../../../flutter/shell/profiling/sampling_profiler.cc
 FILE: ../../../flutter/shell/profiling/sampling_profiler.h
 FILE: ../../../flutter/shell/profiling/sampling_profiler_unittest.cc
diff --git a/shell/platform/windows/BUILD.gn b/shell/platform/windows/BUILD.gn
index 53b997f5847c4..42f4c16f73bf8 100644
--- a/shell/platform/windows/BUILD.gn
+++ b/shell/platform/windows/BUILD.gn
@@ -111,6 +111,7 @@ source_set("flutter_windows_source") {
     "windows_proc_table.h",
     "windows_registry.cc",
     "windows_registry.h",
+    "windowsx_shim.h",
   ]
 
   libs = [
diff --git a/shell/platform/windows/accessibility_bridge_windows.cc b/shell/platform/windows/accessibility_bridge_windows.cc
index add1fc7f7c036..83435ce3a41b1 100644
--- a/shell/platform/windows/accessibility_bridge_windows.cc
+++ b/shell/platform/windows/accessibility_bridge_windows.cc
@@ -31,53 +31,67 @@ void AccessibilityBridgeWindows::OnAccessibilityEvent(
 
   switch (event_type) {
     case ui::AXEventGenerator::Event::ALERT:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_SYSTEM_ALERT);
+      DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kAlert);
       break;
     case ui::AXEventGenerator::Event::CHECKED_STATE_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_VALUECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kValueChanged);
       break;
     case ui::AXEventGenerator::Event::CHILDREN_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_REORDER);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kChildrenChanged);
+      break;
+    case ui::AXEventGenerator::Event::DOCUMENT_SELECTION_CHANGED:
+      DispatchWinAccessibilityEvent(
+          win_delegate, ax::mojom::Event::kDocumentSelectionChanged);
       break;
     case ui::AXEventGenerator::Event::FOCUS_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_FOCUS);
+      DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kFocus);
       SetFocus(win_delegate);
       break;
     case ui::AXEventGenerator::Event::IGNORED_CHANGED:
       if (ax_node->IsIgnored()) {
-        DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_HIDE);
+        DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kHide);
       }
       break;
     case ui::AXEventGenerator::Event::IMAGE_ANNOTATION_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_NAMECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kTextChanged);
       break;
     case ui::AXEventGenerator::Event::LIVE_REGION_CHANGED:
       DispatchWinAccessibilityEvent(win_delegate,
-                                    EVENT_OBJECT_LIVEREGIONCHANGED);
+                                    ax::mojom::Event::kLiveRegionChanged);
       break;
     case ui::AXEventGenerator::Event::NAME_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_NAMECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kTextChanged);
       break;
     case ui::AXEventGenerator::Event::SCROLL_HORIZONTAL_POSITION_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_SYSTEM_SCROLLINGEND);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kScrollPositionChanged);
       break;
     case ui::AXEventGenerator::Event::SCROLL_VERTICAL_POSITION_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_SYSTEM_SCROLLINGEND);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kScrollPositionChanged);
       break;
     case ui::AXEventGenerator::Event::SELECTED_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_VALUECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kValueChanged);
       break;
     case ui::AXEventGenerator::Event::SELECTED_CHILDREN_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_SELECTIONWITHIN);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kSelectedChildrenChanged);
       break;
     case ui::AXEventGenerator::Event::SUBTREE_CREATED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_SHOW);
+      DispatchWinAccessibilityEvent(win_delegate, ax::mojom::Event::kShow);
       break;
     case ui::AXEventGenerator::Event::VALUE_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_VALUECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kValueChanged);
       break;
     case ui::AXEventGenerator::Event::WIN_IACCESSIBLE_STATE_CHANGED:
-      DispatchWinAccessibilityEvent(win_delegate, EVENT_OBJECT_STATECHANGE);
+      DispatchWinAccessibilityEvent(win_delegate,
+                                    ax::mojom::Event::kStateChanged);
       break;
     case ui::AXEventGenerator::Event::ACCESS_KEY_CHANGED:
     case ui::AXEventGenerator::Event::ACTIVE_DESCENDANT_CHANGED:
@@ -90,7 +104,6 @@ void AccessibilityBridgeWindows::OnAccessibilityEvent(
     case ui::AXEventGenerator::Event::CONTROLS_CHANGED:
     case ui::AXEventGenerator::Event::DESCRIBED_BY_CHANGED:
     case ui::AXEventGenerator::Event::DESCRIPTION_CHANGED:
-    case ui::AXEventGenerator::Event::DOCUMENT_SELECTION_CHANGED:
     case ui::AXEventGenerator::Event::DOCUMENT_TITLE_CHANGED:
     case ui::AXEventGenerator::Event::DROPEFFECT_CHANGED:
     case ui::AXEventGenerator::Event::ENABLED_CHANGED:
@@ -151,7 +164,7 @@ AccessibilityBridgeWindows::CreateFlutterPlatformNodeDelegate() {
 
 void AccessibilityBridgeWindows::DispatchWinAccessibilityEvent(
     std::shared_ptr<FlutterPlatformNodeDelegateWindows> node_delegate,
-    DWORD event_type) {
+    ax::mojom::Event event_type) {
   node_delegate->DispatchWinAccessibilityEvent(event_type);
 }
 
@@ -160,4 +173,18 @@ void AccessibilityBridgeWindows::SetFocus(
   node_delegate->SetFocus();
 }
 
+gfx::NativeViewAccessible
+AccessibilityBridgeWindows::GetChildOfAXFragmentRoot() {
+  return view_->GetNativeViewAccessible();
+}
+
+gfx::NativeViewAccessible
+AccessibilityBridgeWindows::GetParentOfAXFragmentRoot() {
+  return nullptr;
+}
+
+bool AccessibilityBridgeWindows::IsAXFragmentRootAControlElement() {
+  return true;
+}
+
 }  // namespace flutter
diff --git a/shell/platform/windows/accessibility_bridge_windows.h b/shell/platform/windows/accessibility_bridge_windows.h
index 68f75298a83e9..9f32b5ed666fa 100644
--- a/shell/platform/windows/accessibility_bridge_windows.h
+++ b/shell/platform/windows/accessibility_bridge_windows.h
@@ -6,13 +6,12 @@
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_ACCESSIBILITY_BRIDGE_WINDOWS_H_
 
 #include "flutter/shell/platform/common/accessibility_bridge.h"
-
-#include "flutter/shell/platform/windows/flutter_windows_engine.h"
-#include "flutter/shell/platform/windows/flutter_windows_view.h"
+#include "flutter/third_party/accessibility/ax/platform/ax_fragment_root_delegate_win.h"
 
 namespace flutter {
 
 class FlutterWindowsEngine;
+class FlutterWindowsView;
 class FlutterPlatformNodeDelegateWindows;
 
 // The Win32 implementation of AccessibilityBridge.
@@ -24,7 +23,8 @@ class FlutterPlatformNodeDelegateWindows;
 ///
 /// AccessibilityBridgeWindows must be created as a shared_ptr, since some
 /// methods acquires its weak_ptr.
-class AccessibilityBridgeWindows : public AccessibilityBridge {
+class AccessibilityBridgeWindows : public AccessibilityBridge,
+                                   public ui::AXFragmentRootDelegateWin {
  public:
   AccessibilityBridgeWindows(FlutterWindowsEngine* engine,
                              FlutterWindowsView* view);
@@ -41,7 +41,7 @@ class AccessibilityBridgeWindows : public AccessibilityBridge {
   // This is a virtual method for the convenience of unit tests.
   virtual void DispatchWinAccessibilityEvent(
       std::shared_ptr<FlutterPlatformNodeDelegateWindows> node_delegate,
-      DWORD event_type);
+      ax::mojom::Event event_type);
 
   // Sets the accessibility focus to the accessibility node associated with the
   // specified semantics node.
@@ -50,6 +50,15 @@ class AccessibilityBridgeWindows : public AccessibilityBridge {
   virtual void SetFocus(
       std::shared_ptr<FlutterPlatformNodeDelegateWindows> node_delegate);
 
+  // |AXFragmentRootDelegateWin|
+  gfx::NativeViewAccessible GetChildOfAXFragmentRoot() override;
+
+  // |AXFragmentRootDelegateWin|
+  gfx::NativeViewAccessible GetParentOfAXFragmentRoot() override;
+
+  // |AXFragmentRootDelegateWin|
+  bool IsAXFragmentRootAControlElement() override;
+
  protected:
   // |AccessibilityBridge|
   void OnAccessibilityEvent(
diff --git a/shell/platform/windows/accessibility_bridge_windows_unittests.cc b/shell/platform/windows/accessibility_bridge_windows_unittests.cc
index 2dae9d8b41e01..e3cc3b58a0f98 100644
--- a/shell/platform/windows/accessibility_bridge_windows_unittests.cc
+++ b/shell/platform/windows/accessibility_bridge_windows_unittests.cc
@@ -29,7 +29,7 @@ namespace {
 // A structure representing a Win32 MSAA event targeting a specified node.
 struct MsaaEvent {
   std::shared_ptr<FlutterPlatformNodeDelegateWindows> node_delegate;
-  DWORD event_type;
+  ax::mojom::Event event_type;
 };
 
 // Accessibility bridge delegate that captures events dispatched to the OS.
@@ -43,7 +43,7 @@ class AccessibilityBridgeWindowsSpy : public AccessibilityBridgeWindows {
 
   void DispatchWinAccessibilityEvent(
       std::shared_ptr<FlutterPlatformNodeDelegateWindows> node_delegate,
-      DWORD event_type) override {
+      ax::mojom::Event event_type) override {
     dispatched_events_.push_back({node_delegate, event_type});
   }
 
@@ -76,7 +76,7 @@ class FlutterWindowsEngineSpy : public FlutterWindowsEngine {
       : FlutterWindowsEngine(project) {}
 
  protected:
-  virtual std::shared_ptr<AccessibilityBridge> CreateAccessibilityBridge(
+  virtual std::shared_ptr<AccessibilityBridgeWindows> CreateAccessibilityBridge(
       FlutterWindowsEngine* engine,
       FlutterWindowsView* view) override {
     return std::make_shared<AccessibilityBridgeWindowsSpy>(engine, view);
@@ -169,7 +169,7 @@ std::shared_ptr<AccessibilityBridgeWindowsSpy> GetAccessibilityBridgeSpy(
 
 void ExpectWinEventFromAXEvent(int32_t node_id,
                                ui::AXEventGenerator::Event ax_event,
-                               DWORD expected_event) {
+                               ax::mojom::Event expected_event) {
   auto window_binding_handler =
       std::make_unique<::testing::NiceMock<MockWindowBindingHandler>>();
   FlutterWindowsView view(std::move(window_binding_handler));
@@ -246,12 +246,12 @@ TEST(AccessibilityBridgeWindows, DispatchAccessibilityAction) {
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityEventAlert) {
   ExpectWinEventFromAXEvent(0, ui::AXEventGenerator::Event::ALERT,
-                            EVENT_SYSTEM_ALERT);
+                            ax::mojom::Event::kAlert);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityEventChildrenChanged) {
   ExpectWinEventFromAXEvent(0, ui::AXEventGenerator::Event::CHILDREN_CHANGED,
-                            EVENT_OBJECT_REORDER);
+                            ax::mojom::Event::kChildrenChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityEventFocusChanged) {
@@ -270,7 +270,8 @@ TEST(AccessibilityBridgeWindows, OnAccessibilityEventFocusChanged) {
                                  ax::mojom::EventFrom::kNone,
                                  {}}});
   ASSERT_EQ(bridge->dispatched_events().size(), 1);
-  EXPECT_EQ(bridge->dispatched_events()[0].event_type, EVENT_OBJECT_FOCUS);
+  EXPECT_EQ(bridge->dispatched_events()[0].event_type,
+            ax::mojom::Event::kFocus);
 
   ASSERT_EQ(bridge->focused_nodes().size(), 1);
   EXPECT_EQ(bridge->focused_nodes()[0], 1);
@@ -279,62 +280,62 @@ TEST(AccessibilityBridgeWindows, OnAccessibilityEventFocusChanged) {
 TEST(AccessibilityBridgeWindows, OnAccessibilityEventIgnoredChanged) {
   // Static test nodes with no text, hint, or scrollability are ignored.
   ExpectWinEventFromAXEvent(4, ui::AXEventGenerator::Event::IGNORED_CHANGED,
-                            EVENT_OBJECT_HIDE);
+                            ax::mojom::Event::kHide);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityImageAnnotationChanged) {
   ExpectWinEventFromAXEvent(
       1, ui::AXEventGenerator::Event::IMAGE_ANNOTATION_CHANGED,
-      EVENT_OBJECT_NAMECHANGE);
+      ax::mojom::Event::kTextChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityLiveRegionChanged) {
   ExpectWinEventFromAXEvent(1, ui::AXEventGenerator::Event::LIVE_REGION_CHANGED,
-                            EVENT_OBJECT_LIVEREGIONCHANGED);
+                            ax::mojom::Event::kLiveRegionChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityNameChanged) {
   ExpectWinEventFromAXEvent(1, ui::AXEventGenerator::Event::NAME_CHANGED,
-                            EVENT_OBJECT_NAMECHANGE);
+                            ax::mojom::Event::kTextChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityHScrollPosChanged) {
   ExpectWinEventFromAXEvent(
       1, ui::AXEventGenerator::Event::SCROLL_HORIZONTAL_POSITION_CHANGED,
-      EVENT_SYSTEM_SCROLLINGEND);
+      ax::mojom::Event::kScrollPositionChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityVScrollPosChanged) {
   ExpectWinEventFromAXEvent(
       1, ui::AXEventGenerator::Event::SCROLL_VERTICAL_POSITION_CHANGED,
-      EVENT_SYSTEM_SCROLLINGEND);
+      ax::mojom::Event::kScrollPositionChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilitySelectedChanged) {
   ExpectWinEventFromAXEvent(1, ui::AXEventGenerator::Event::SELECTED_CHANGED,
-                            EVENT_OBJECT_VALUECHANGE);
+                            ax::mojom::Event::kValueChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilitySelectedChildrenChanged) {
   ExpectWinEventFromAXEvent(
       2, ui::AXEventGenerator::Event::SELECTED_CHILDREN_CHANGED,
-      EVENT_OBJECT_SELECTIONWITHIN);
+      ax::mojom::Event::kSelectedChildrenChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilitySubtreeCreated) {
   ExpectWinEventFromAXEvent(0, ui::AXEventGenerator::Event::SUBTREE_CREATED,
-                            EVENT_OBJECT_SHOW);
+                            ax::mojom::Event::kShow);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityValueChanged) {
   ExpectWinEventFromAXEvent(1, ui::AXEventGenerator::Event::VALUE_CHANGED,
-                            EVENT_OBJECT_VALUECHANGE);
+                            ax::mojom::Event::kValueChanged);
 }
 
 TEST(AccessibilityBridgeWindows, OnAccessibilityStateChanged) {
   ExpectWinEventFromAXEvent(
       1, ui::AXEventGenerator::Event::WIN_IACCESSIBLE_STATE_CHANGED,
-      EVENT_OBJECT_STATECHANGE);
+      ax::mojom::Event::kStateChanged);
 }
 
 }  // namespace testing
diff --git a/shell/platform/windows/flutter_platform_node_delegate_windows.cc b/shell/platform/windows/flutter_platform_node_delegate_windows.cc
index 5f5ad62d4adcd..a7c972be10a62 100644
--- a/shell/platform/windows/flutter_platform_node_delegate_windows.cc
+++ b/shell/platform/windows/flutter_platform_node_delegate_windows.cc
@@ -10,6 +10,7 @@
 #include "flutter/shell/platform/windows/flutter_windows_view.h"
 #include "flutter/third_party/accessibility/ax/ax_clipping_behavior.h"
 #include "flutter/third_party/accessibility/ax/ax_coordinate_system.h"
+#include "flutter/third_party/accessibility/ax/platform/ax_fragment_root_win.h"
 
 namespace flutter {
 
@@ -90,14 +91,8 @@ gfx::Rect FlutterPlatformNodeDelegateWindows::GetBoundsRect(
 }
 
 void FlutterPlatformNodeDelegateWindows::DispatchWinAccessibilityEvent(
-    DWORD event_type) {
-  HWND hwnd = view_->GetPlatformWindow();
-  if (!hwnd) {
-    return;
-  }
-  assert(ax_platform_node_);
-  ::NotifyWinEvent(event_type, hwnd, OBJID_CLIENT,
-                   -ax_platform_node_->GetUniqueId());
+    ax::mojom::Event event_type) {
+  ax_platform_node_->NotifyAccessibilityEvent(event_type);
 }
 
 void FlutterPlatformNodeDelegateWindows::SetFocus() {
@@ -107,4 +102,9 @@ void FlutterPlatformNodeDelegateWindows::SetFocus() {
   GetNativeViewAccessible()->accSelect(SELFLAG_TAKEFOCUS, varchild);
 }
 
+gfx::AcceleratedWidget
+FlutterPlatformNodeDelegateWindows::GetTargetForNativeAccessibilityEvent() {
+  return view_->GetPlatformWindow();
+}
+
 }  // namespace flutter
diff --git a/shell/platform/windows/flutter_platform_node_delegate_windows.h b/shell/platform/windows/flutter_platform_node_delegate_windows.h
index 8bac155b9c14d..364411cfffeab 100644
--- a/shell/platform/windows/flutter_platform_node_delegate_windows.h
+++ b/shell/platform/windows/flutter_platform_node_delegate_windows.h
@@ -42,12 +42,15 @@ class FlutterPlatformNodeDelegateWindows : public FlutterPlatformNodeDelegate {
   // Dispatches a Windows accessibility event of the specified type, generated
   // by the accessibility node associated with this object. This is a
   // convenience wrapper around |NotifyWinEvent|.
-  virtual void DispatchWinAccessibilityEvent(DWORD event_type);
+  virtual void DispatchWinAccessibilityEvent(ax::mojom::Event event_type);
 
   // Sets the accessibility focus to the accessibility node associated with
   // this object.
   void SetFocus();
 
+  // | AXPlatformNodeDelegate |
+  gfx::AcceleratedWidget GetTargetForNativeAccessibilityEvent() override;
+
  private:
   ui::AXPlatformNode* ax_platform_node_;
   std::weak_ptr<AccessibilityBridge> bridge_;
diff --git a/shell/platform/windows/flutter_window.cc b/shell/platform/windows/flutter_window.cc
index 165fd52413a8d..18e7210bedda6 100644
--- a/shell/platform/windows/flutter_window.cc
+++ b/shell/platform/windows/flutter_window.cc
@@ -303,4 +303,8 @@ AccessibilityRootNode* FlutterWindow::GetAccessibilityRootNode() {
   return accessibility_root_;
 }
 
+ui::AXFragmentRootDelegateWin* FlutterWindow::GetAxFragmentRootDelegate() {
+  return binding_handler_delegate_->GetAxFragmentRootDelegate();
+}
+
 }  // namespace flutter
diff --git a/shell/platform/windows/flutter_window.h b/shell/platform/windows/flutter_window.h
index b8f3183bcbd4f..e80d98b801d6d 100644
--- a/shell/platform/windows/flutter_window.h
+++ b/shell/platform/windows/flutter_window.h
@@ -5,8 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_H_
 
-#include <windowsx.h>
-
 #include <iostream>
 #include <string>
 #include <vector>
@@ -154,6 +152,9 @@ class FlutterWindow : public Window, public WindowBindingHandler {
   // |WindowBindingHandler|
   AccessibilityRootNode* GetAccessibilityRootNode() override;
 
+  // |Window|
+  ui::AXFragmentRootDelegateWin* GetAxFragmentRootDelegate() override;
+
  private:
   // A pointer to a FlutterWindowsView that can be used to update engine
   // windowing and input state.
diff --git a/shell/platform/windows/flutter_windows_engine.cc b/shell/platform/windows/flutter_windows_engine.cc
index 795d83efea6fd..5118f1e39d5bb 100644
--- a/shell/platform/windows/flutter_windows_engine.cc
+++ b/shell/platform/windows/flutter_windows_engine.cc
@@ -618,7 +618,7 @@ void FlutterWindowsEngine::UpdateSemanticsEnabled(bool enabled) {
   }
 }
 
-std::shared_ptr<AccessibilityBridge>
+std::shared_ptr<AccessibilityBridgeWindows>
 FlutterWindowsEngine::CreateAccessibilityBridge(FlutterWindowsEngine* engine,
                                                 FlutterWindowsView* view) {
   return std::make_shared<AccessibilityBridgeWindows>(engine, view);
diff --git a/shell/platform/windows/flutter_windows_engine.h b/shell/platform/windows/flutter_windows_engine.h
index d7f08036c552c..193cc8f03f520 100644
--- a/shell/platform/windows/flutter_windows_engine.h
+++ b/shell/platform/windows/flutter_windows_engine.h
@@ -19,6 +19,7 @@
 #include "flutter/shell/platform/common/client_wrapper/include/flutter/basic_message_channel.h"
 #include "flutter/shell/platform/common/incoming_message_dispatcher.h"
 #include "flutter/shell/platform/embedder/embedder.h"
+#include "flutter/shell/platform/windows/accessibility_bridge_windows.h"
 #include "flutter/shell/platform/windows/angle_surface_manager.h"
 #include "flutter/shell/platform/windows/flutter_desktop_messenger.h"
 #include "flutter/shell/platform/windows/flutter_project_bundle.h"
@@ -142,7 +143,7 @@ class FlutterWindowsEngine {
   // rendering using software instead of OpenGL.
   AngleSurfaceManager* surface_manager() { return surface_manager_.get(); }
 
-  std::weak_ptr<AccessibilityBridge> accessibility_bridge() {
+  std::weak_ptr<AccessibilityBridgeWindows> accessibility_bridge() {
     return accessibility_bridge_;
   }
 
@@ -251,7 +252,7 @@ class FlutterWindowsEngine {
   //
   // By default this method calls AccessibilityBridge's constructor. Exposing
   // this method allows unit tests to override in order to capture information.
-  virtual std::shared_ptr<AccessibilityBridge> CreateAccessibilityBridge(
+  virtual std::shared_ptr<AccessibilityBridgeWindows> CreateAccessibilityBridge(
       FlutterWindowsEngine* engine,
       FlutterWindowsView* view);
 
@@ -333,7 +334,7 @@ class FlutterWindowsEngine {
 
   bool high_contrast_enabled_ = false;
 
-  std::shared_ptr<AccessibilityBridge> accessibility_bridge_;
+  std::shared_ptr<AccessibilityBridgeWindows> accessibility_bridge_;
 
   // The manager for WindowProc delegate registration and callbacks.
   std::unique_ptr<WindowProcDelegateManager> window_proc_delegate_manager_;
diff --git a/shell/platform/windows/flutter_windows_view.cc b/shell/platform/windows/flutter_windows_view.cc
index a7b9a675d6b58..65ae0ef3cef40 100644
--- a/shell/platform/windows/flutter_windows_view.cc
+++ b/shell/platform/windows/flutter_windows_view.cc
@@ -675,4 +675,8 @@ void FlutterWindowsView::NotifyWinEventWrapper(DWORD event,
   }
 }
 
+ui::AXFragmentRootDelegateWin* FlutterWindowsView::GetAxFragmentRootDelegate() {
+  return engine_->accessibility_bridge().lock().get();
+}
+
 }  // namespace flutter
diff --git a/shell/platform/windows/flutter_windows_view.h b/shell/platform/windows/flutter_windows_view.h
index 1c7d721e2f5eb..2c0c719953f7c 100644
--- a/shell/platform/windows/flutter_windows_view.h
+++ b/shell/platform/windows/flutter_windows_view.h
@@ -5,8 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOWS_VIEW_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOWS_VIEW_H_
 
-#include <windowsx.h>
-
 #include <memory>
 #include <mutex>
 #include <string>
@@ -197,6 +195,9 @@ class FlutterWindowsView : public WindowBindingHandlerDelegate,
   // |TextInputPluginDelegate|
   void OnResetImeComposing() override;
 
+  // |WindowBindingHandlerDelegate|
+  virtual ui::AXFragmentRootDelegateWin* GetAxFragmentRootDelegate() override;
+
  protected:
   // Called to create keyboard key handler.
   //
diff --git a/shell/platform/windows/flutter_windows_view_unittests.cc b/shell/platform/windows/flutter_windows_view_unittests.cc
index f2699206f0daf..0c1aa369fbe7d 100644
--- a/shell/platform/windows/flutter_windows_view_unittests.cc
+++ b/shell/platform/windows/flutter_windows_view_unittests.cc
@@ -4,6 +4,7 @@
 
 #include "flutter/shell/platform/windows/flutter_windows_view.h"
 
+#include <UIAutomation.h>
 #include <comdef.h>
 #include <comutil.h>
 #include <oleacc.h>
@@ -231,6 +232,33 @@ TEST(FlutterWindowsView, AddSemanticsNodeUpdate) {
   varrole.vt = VT_I4;
   ASSERT_EQ(native_view->get_accRole(varchild, &varrole), S_OK);
   EXPECT_EQ(varrole.lVal, ROLE_SYSTEM_STATICTEXT);
+
+  // Get the IRawElementProviderFragment object.
+  IRawElementProviderSimple* uia_view;
+  native_view->QueryInterface(IID_PPV_ARGS(&uia_view));
+  ASSERT_TRUE(uia_view != nullptr);
+
+  // Verify name property matches our label.
+  VARIANT varname{};
+  ASSERT_EQ(uia_view->GetPropertyValue(UIA_NamePropertyId, &varname), S_OK);
+  EXPECT_EQ(varname.vt, VT_BSTR);
+  name = _com_util::ConvertBSTRToString(varname.bstrVal);
+  EXPECT_EQ(name, "name");
+
+  // Verify value property matches our label.
+  VARIANT varvalue{};
+  ASSERT_EQ(uia_view->GetPropertyValue(UIA_ValueValuePropertyId, &varvalue),
+            S_OK);
+  EXPECT_EQ(varvalue.vt, VT_BSTR);
+  value = _com_util::ConvertBSTRToString(varvalue.bstrVal);
+  EXPECT_EQ(value, "value");
+
+  // Verify node control type is text.
+  varrole = {};
+  ASSERT_EQ(uia_view->GetPropertyValue(UIA_ControlTypePropertyId, &varrole),
+            S_OK);
+  EXPECT_EQ(varrole.vt, VT_I4);
+  EXPECT_EQ(varrole.lVal, UIA_TextControlTypeId);
 }
 
 // Verify the native IAccessible COM object tree is an accurate reflection of
@@ -660,6 +688,17 @@ TEST(FlutterWindowsViewTest, CheckboxNativeState) {
     VARIANT native_state = {};
     ASSERT_TRUE(SUCCEEDED(native_view->get_accState(varchild, &native_state)));
     EXPECT_TRUE(native_state.lVal & STATE_SYSTEM_CHECKED);
+
+    // Perform similar tests for UIA value;
+    IRawElementProviderSimple* uia_node;
+    native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_ToggleToggleStatePropertyId, &native_state)));
+    EXPECT_EQ(native_state.lVal, ToggleState_On);
+
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_AriaPropertiesPropertyId, &native_state)));
+    EXPECT_NE(std::wcsstr(native_state.bstrVal, L"checked=true"), nullptr);
   }
 
   // Test unchecked too.
@@ -690,6 +729,17 @@ TEST(FlutterWindowsViewTest, CheckboxNativeState) {
     VARIANT native_state = {};
     ASSERT_TRUE(SUCCEEDED(native_view->get_accState(varchild, &native_state)));
     EXPECT_FALSE(native_state.lVal & STATE_SYSTEM_CHECKED);
+
+    // Perform similar tests for UIA value;
+    IRawElementProviderSimple* uia_node;
+    native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_ToggleToggleStatePropertyId, &native_state)));
+    EXPECT_EQ(native_state.lVal, ToggleState_Off);
+
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_AriaPropertiesPropertyId, &native_state)));
+    EXPECT_NE(std::wcsstr(native_state.bstrVal, L"checked=false"), nullptr);
   }
 
   // Now check mixed state.
@@ -721,6 +771,17 @@ TEST(FlutterWindowsViewTest, CheckboxNativeState) {
     VARIANT native_state = {};
     ASSERT_TRUE(SUCCEEDED(native_view->get_accState(varchild, &native_state)));
     EXPECT_TRUE(native_state.lVal & STATE_SYSTEM_MIXED);
+
+    // Perform similar tests for UIA value;
+    IRawElementProviderSimple* uia_node;
+    native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_ToggleToggleStatePropertyId, &native_state)));
+    EXPECT_EQ(native_state.lVal, ToggleState_Indeterminate);
+
+    ASSERT_TRUE(SUCCEEDED(uia_node->GetPropertyValue(
+        UIA_AriaPropertiesPropertyId, &native_state)));
+    EXPECT_NE(std::wcsstr(native_state.bstrVal, L"checked=mixed"), nullptr);
   }
 }
 
@@ -788,6 +849,21 @@ TEST(FlutterWindowsViewTest, SwitchNativeState) {
     VARIANT native_state = {};
     ASSERT_TRUE(SUCCEEDED(native_view->get_accState(varchild, &native_state)));
     EXPECT_TRUE(native_state.lVal & STATE_SYSTEM_PRESSED);
+
+    // Test similarly on UIA node.
+    IRawElementProviderSimple* uia_node;
+    native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+    ASSERT_EQ(uia_node->GetPropertyValue(UIA_ControlTypePropertyId, &varrole),
+              S_OK);
+    EXPECT_EQ(varrole.lVal, UIA_ButtonControlTypeId);
+    ASSERT_EQ(uia_node->GetPropertyValue(UIA_ToggleToggleStatePropertyId,
+                                         &native_state),
+              S_OK);
+    EXPECT_EQ(native_state.lVal, ToggleState_On);
+    ASSERT_EQ(
+        uia_node->GetPropertyValue(UIA_AriaPropertiesPropertyId, &native_state),
+        S_OK);
+    EXPECT_NE(std::wcsstr(native_state.bstrVal, L"pressed=true"), nullptr);
   }
 
   // Test unpressed too.
@@ -818,6 +894,18 @@ TEST(FlutterWindowsViewTest, SwitchNativeState) {
     VARIANT native_state = {};
     ASSERT_TRUE(SUCCEEDED(native_view->get_accState(varchild, &native_state)));
     EXPECT_FALSE(native_state.lVal & STATE_SYSTEM_PRESSED);
+
+    // Test similarly on UIA node.
+    IRawElementProviderSimple* uia_node;
+    native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+    ASSERT_EQ(uia_node->GetPropertyValue(UIA_ToggleToggleStatePropertyId,
+                                         &native_state),
+              S_OK);
+    EXPECT_EQ(native_state.lVal, ToggleState_Off);
+    ASSERT_EQ(
+        uia_node->GetPropertyValue(UIA_AriaPropertiesPropertyId, &native_state),
+        S_OK);
+    EXPECT_NE(std::wcsstr(native_state.bstrVal, L"pressed=false"), nullptr);
   }
 }
 
@@ -862,6 +950,25 @@ TEST(FlutterWindowsViewTest, TooltipNodeData) {
   std::string tooltip = root_node->GetData().GetStringAttribute(
       ax::mojom::StringAttribute::kTooltip);
   EXPECT_EQ(tooltip, "tooltip");
+
+  // Check that MSAA name contains the tooltip.
+  IAccessible* native_view = bridge
+                                 ->GetFlutterPlatformNodeDelegateFromID(
+                                     AccessibilityBridge::kRootNodeId)
+                                 .lock()
+                                 ->GetNativeViewAccessible();
+  VARIANT varchild = {.vt = VT_I4, .lVal = CHILDID_SELF};
+  BSTR bname;
+  ASSERT_EQ(native_view->get_accName(varchild, &bname), S_OK);
+  EXPECT_NE(std::wcsstr(bname, L"tooltip"), nullptr);
+
+  // Check that UIA help text is equal to the tooltip.
+  IRawElementProviderSimple* uia_node;
+  native_view->QueryInterface(IID_PPV_ARGS(&uia_node));
+  VARIANT varname{};
+  ASSERT_EQ(uia_node->GetPropertyValue(UIA_HelpTextPropertyId, &varname), S_OK);
+  std::string uia_tooltip = _com_util::ConvertBSTRToString(varname.bstrVal);
+  EXPECT_EQ(uia_tooltip, "tooltip");
 }
 
 }  // namespace testing
diff --git a/shell/platform/windows/testing/mock_text_input_manager.h b/shell/platform/windows/testing/mock_text_input_manager.h
index 7fefa1ae25170..e51d218273207 100644
--- a/shell/platform/windows/testing/mock_text_input_manager.h
+++ b/shell/platform/windows/testing/mock_text_input_manager.h
@@ -5,7 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_TEXT_INPUT_MANAGER_WIN32_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_TEXT_INPUT_MANAGER_WIN32_H_
 
-#include <windowsx.h>
 #include <cstring>
 #include <optional>
 
diff --git a/shell/platform/windows/testing/mock_window.h b/shell/platform/windows/testing/mock_window.h
index fc50235745e3b..78fabc663c1cf 100644
--- a/shell/platform/windows/testing/mock_window.h
+++ b/shell/platform/windows/testing/mock_window.h
@@ -5,8 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_WIN32_WINDOW_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_WIN32_WINDOW_H_
 
-#include <windowsx.h>
-
 #include "flutter/shell/platform/windows/testing/test_keyboard.h"
 #include "flutter/shell/platform/windows/window.h"
 #include "gmock/gmock.h"
@@ -67,6 +65,8 @@ class MockWindow : public Window {
 
   MOCK_METHOD0(OnThemeChange, void());
 
+  MOCK_METHOD0(GetAxFragmentRootDelegate, ui::AXFragmentRootDelegateWin*());
+
   void CallOnImeComposition(UINT const message,
                             WPARAM const wparam,
                             LPARAM const lparam);
diff --git a/shell/platform/windows/testing/mock_window_binding_handler.h b/shell/platform/windows/testing/mock_window_binding_handler.h
index dcbbc9e15f2a6..2fc5cbd77e905 100644
--- a/shell/platform/windows/testing/mock_window_binding_handler.h
+++ b/shell/platform/windows/testing/mock_window_binding_handler.h
@@ -5,8 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_WINDOW_BINDING_HANDLER_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_TESTING_MOCK_WINDOW_BINDING_HANDLER_H_
 
-#include <windowsx.h>
-
 #include "flutter/shell/platform/windows/window_binding_handler.h"
 #include "gmock/gmock.h"
 
diff --git a/shell/platform/windows/testing/mock_window_binding_handler_delegate.h b/shell/platform/windows/testing/mock_window_binding_handler_delegate.h
index 03534b2e5ecfd..2e7df003cc847 100644
--- a/shell/platform/windows/testing/mock_window_binding_handler_delegate.h
+++ b/shell/platform/windows/testing/mock_window_binding_handler_delegate.h
@@ -63,6 +63,8 @@ class MockWindowBindingHandlerDelegate : public WindowBindingHandlerDelegate {
   MOCK_METHOD1(OnScrollInertiaCancel, void(int32_t));
   MOCK_METHOD0(OnPlatformBrightnessChanged, void());
   MOCK_METHOD1(UpdateHighContrastEnabled, void(bool enabled));
+
+  MOCK_METHOD0(GetAxFragmentRootDelegate, ui::AXFragmentRootDelegateWin*());
 };
 
 }  // namespace testing
diff --git a/shell/platform/windows/testing/test_keyboard.cc b/shell/platform/windows/testing/test_keyboard.cc
index 06a5b86c38409..d752f027c80c0 100644
--- a/shell/platform/windows/testing/test_keyboard.cc
+++ b/shell/platform/windows/testing/test_keyboard.cc
@@ -7,7 +7,6 @@
 #include "flutter/shell/platform/embedder/test_utils/proc_table_replacement.h"
 
 #include <rapidjson/document.h>
-#include <windowsx.h>
 
 namespace flutter {
 namespace testing {
diff --git a/shell/platform/windows/testing/wm_builders.h b/shell/platform/windows/testing/wm_builders.h
index 6f93b13d1c61a..49b78035b7e01 100644
--- a/shell/platform/windows/testing/wm_builders.h
+++ b/shell/platform/windows/testing/wm_builders.h
@@ -7,7 +7,6 @@
 
 #include <stdint.h>
 #include <windows.h>
-#include <windowsx.h>
 
 namespace flutter {
 namespace testing {
diff --git a/shell/platform/windows/window.cc b/shell/platform/windows/window.cc
index a6fe97b0d5383..8f2a3327a97db 100644
--- a/shell/platform/windows/window.cc
+++ b/shell/platform/windows/window.cc
@@ -59,7 +59,8 @@ Window::Window(std::unique_ptr<WindowsProcTable> windows_proc_table,
     : touch_id_generator_(kMinTouchDeviceId, kMaxTouchDeviceId),
       windows_proc_table_(std::move(windows_proc_table)),
       text_input_manager_(std::move(text_input_manager)),
-      accessibility_root_(nullptr) {
+      accessibility_root_(nullptr),
+      ax_fragment_root_(nullptr) {
   // Get the DPI of the primary monitor as the initial DPI. If Per-Monitor V2 is
   // supported, |current_dpi_| should be updated in the
   // kWmDpiChangedBeforeParent message.
@@ -200,9 +201,27 @@ LRESULT Window::OnGetObject(UINT const message,
   }
 
   gfx::NativeViewAccessible root_view = GetNativeViewAccessible();
+  // TODO(schectman): UIA is currently disabled by default.
+  // https://github.com/flutter/flutter/issues/114547
   if (is_uia_request && root_view) {
-    // TODO(cbracken): https://github.com/flutter/flutter/issues/94782
-    // Implement when we adopt UIA support.
+#ifdef FLUTTER_ENGINE_USE_UIA
+    if (!ax_fragment_root_) {
+      ax_fragment_root_ = std::make_unique<ui::AXFragmentRootWin>(
+          window_handle_, GetAxFragmentRootDelegate());
+    }
+
+    // Retrieve UIA object for the root view.
+    Microsoft::WRL::ComPtr<IRawElementProviderSimple> root;
+    if (SUCCEEDED(ax_fragment_root_->GetNativeViewAccessible()->QueryInterface(
+            IID_PPV_ARGS(&root)))) {
+      // Return the UIA object via UiaReturnRawElementProvider(). See:
+      // https://docs.microsoft.com/en-us/windows/win32/winauto/wm-getobject
+      reference_result = UiaReturnRawElementProvider(window_handle_, wparam,
+                                                     lparam, root.Get());
+    } else {
+      FML_LOG(ERROR) << "Failed to query AX fragment root.";
+    }
+#endif  // FLUTTER_ENGINE_USE_UIA
   } else if (is_msaa_request && root_view) {
     // Create the accessibility root if it does not already exist.
     if (!accessibility_root_) {
@@ -212,10 +231,9 @@ LRESULT Window::OnGetObject(UINT const message,
     // Microsoft::WRL::ComPtr<IAccessible> root(root_view);
     accessibility_root_->SetWindow(root_view);
     Microsoft::WRL::ComPtr<IAccessible> root(accessibility_root_);
-    LRESULT lresult = LresultFromObject(IID_IAccessible, wparam, root.Get());
-    return lresult;
+    reference_result = LresultFromObject(IID_IAccessible, wparam, root.Get());
   }
-  return 0;
+  return reference_result;
 }
 
 void Window::OnImeSetContext(UINT const message,
diff --git a/shell/platform/windows/window.h b/shell/platform/windows/window.h
index ee9af55950b59..6c234ce68fc58 100644
--- a/shell/platform/windows/window.h
+++ b/shell/platform/windows/window.h
@@ -6,7 +6,6 @@
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WIN32_WINDOW_H_
 
 #include <Windows.h>
-#include <Windowsx.h>
 
 #include <map>
 #include <memory>
@@ -20,6 +19,9 @@
 #include "flutter/shell/platform/windows/sequential_id_generator.h"
 #include "flutter/shell/platform/windows/text_input_manager.h"
 #include "flutter/shell/platform/windows/windows_proc_table.h"
+#include "flutter/shell/platform/windows/windowsx_shim.h"
+#include "flutter/third_party/accessibility/ax/platform/ax_fragment_root_delegate_win.h"
+#include "flutter/third_party/accessibility/ax/platform/ax_fragment_root_win.h"
 #include "flutter/third_party/accessibility/gfx/native_widget_types.h"
 
 namespace flutter {
@@ -211,6 +213,9 @@ class Window : public KeyboardManager::WindowDelegate {
   // Check if the high contrast feature is enabled on the OS
   virtual bool GetHighContrastEnabled();
 
+  // Called to obtain a pointer to the fragment root delegate.
+  virtual ui::AXFragmentRootDelegateWin* GetAxFragmentRootDelegate() = 0;
+
  protected:
   // Win32's DefWindowProc.
   //
@@ -299,6 +304,12 @@ class Window : public KeyboardManager::WindowDelegate {
 
   // Timer identifier for DirectManipulation gesture polling.
   const static int kDirectManipulationTimer = 1;
+
+  // Implements IRawElementProviderFragmentRoot when UIA is enabled.
+  std::unique_ptr<ui::AXFragmentRootWin> ax_fragment_root_;
+
+  // Allow WindowAXFragmentRootDelegate to access protected method.
+  friend class WindowAXFragmentRootDelegate;
 };
 
 }  // namespace flutter
diff --git a/shell/platform/windows/window_binding_handler_delegate.h b/shell/platform/windows/window_binding_handler_delegate.h
index 485fe4384f3cc..9d0e0253c447a 100644
--- a/shell/platform/windows/window_binding_handler_delegate.h
+++ b/shell/platform/windows/window_binding_handler_delegate.h
@@ -9,6 +9,7 @@
 
 #include "flutter/shell/platform/common/geometry.h"
 #include "flutter/shell/platform/embedder/embedder.h"
+#include "flutter/third_party/accessibility/ax/platform/ax_fragment_root_delegate_win.h"
 #include "flutter/third_party/accessibility/gfx/native_widget_types.h"
 
 namespace flutter {
@@ -135,6 +136,13 @@ class WindowBindingHandlerDelegate {
 
   // Update the status of the high contrast feature
   virtual void UpdateHighContrastEnabled(bool enabled) = 0;
+
+  // Obtain a pointer to the fragment root delegate.
+  // This is required by UIA in order to obtain the fragment root that
+  // contains a fragment obtained by, for example, a hit test. Unlike
+  // MSAA, UIA elements do not explicitly store or enumerate their
+  // children and parents, so a method such as this is required.
+  virtual ui::AXFragmentRootDelegateWin* GetAxFragmentRootDelegate() = 0;
 };
 
 }  // namespace flutter
diff --git a/shell/platform/windows/windowsx_shim.h b/shell/platform/windows/windowsx_shim.h
new file mode 100644
index 0000000000000..2e3a88fc0522b
--- /dev/null
+++ b/shell/platform/windows/windowsx_shim.h
@@ -0,0 +1,28 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_WIN_WINDOWSX_SHIM_H_
+#define BASE_WIN_WINDOWSX_SHIM_H_
+
+// The Win32 platform header <windowsx.h> contains some macros for
+// common function names. To work around that, windowsx.h is not to be
+// included directly, and instead this file should be included. If one
+// of the removed Win32 macros is wanted, use the expanded form
+// manually instead.
+
+#ifdef _INC_WINDOWS_X
+#error "There is an include of windowsx.h in the code. Use windowsx_shim.h"
+#endif  // _INC_WINDOWS_X
+
+#include <windowsx.h>
+
+#undef GetNextSibling  // Same as GetWindow(hwnd, GW_HWNDNEXT)
+#undef GetFirstChild   // Same as GetTopWindow(hwnd)
+#undef IsMaximized     // Defined to IsZoomed, use IsZoomed directly instead
+#undef IsMinimized     // Defined to IsIconic, use IsIconic directly instead
+#undef IsRestored      // Macro to check that neither WS_MINIMIZE, nor
+                       // WS_MAXIMIZE is set in the GetWindowStyle return
+                       // value.
+
+#endif  // BASE_WIN_WINDOWSX_SHIM_H_
diff --git a/third_party/accessibility/ax/ax_active_popup.cc b/third_party/accessibility/ax/ax_active_popup.cc
index 904de75c4bbb0..d41510bceb157 100644
--- a/third_party/accessibility/ax/ax_active_popup.cc
+++ b/third_party/accessibility/ax/ax_active_popup.cc
@@ -15,7 +15,7 @@ namespace ui {
 static std::optional<int32_t> g_active_popup_ax_unique_id;
 
 std::optional<int32_t> GetActivePopupAxUniqueId() {
-  return *g_active_popup_ax_unique_id;
+  return g_active_popup_ax_unique_id;
 }
 
 void SetActivePopupAxUniqueId(std::optional<int32_t> ax_unique_id) {
diff --git a/third_party/accessibility/ax/platform/ax_platform_node_win.cc b/third_party/accessibility/ax/platform/ax_platform_node_win.cc
index dad8d2739806a..9de6867ad9eed 100644
--- a/third_party/accessibility/ax/platform/ax_platform_node_win.cc
+++ b/third_party/accessibility/ax/platform/ax_platform_node_win.cc
@@ -2465,6 +2465,19 @@ HRESULT AXPlatformNodeWin::GetPropertyValueImpl(PROPERTYID property_id,
       result->intVal = static_cast<int>(ComputeExpandCollapseState());
       break;
 
+    case UIA_ToggleToggleStatePropertyId: {
+      ToggleState state;
+      get_ToggleState(&state);
+      result->vt = VT_I4;
+      result->lVal = state;
+      break;
+    }
+
+    case UIA_ValueValuePropertyId:
+      result->vt = VT_BSTR;
+      result->bstrVal = GetValueAttributeAsBstr(this);
+      break;
+
     // Not currently implemented.
     case UIA_AnnotationObjectsPropertyId:
     case UIA_AnnotationTypesPropertyId:
@@ -5205,6 +5218,8 @@ std::optional<DWORD> AXPlatformNodeWin::MojoEventToMSAAEvent(
       return EVENT_OBJECT_SHOW;
     case ax::mojom::Event::kValueChanged:
       return EVENT_OBJECT_VALUECHANGE;
+    case ax::mojom::Event::kDocumentSelectionChanged:
+      return EVENT_OBJECT_TEXTSELECTIONCHANGED;
     default:
       return std::nullopt;
   }
@@ -5216,6 +5231,8 @@ std::optional<EVENTID> AXPlatformNodeWin::MojoEventToUIAEvent(
   switch (event) {
     case ax::mojom::Event::kAlert:
       return UIA_SystemAlertEventId;
+    case ax::mojom::Event::kDocumentSelectionChanged:
+      return UIA_Text_TextChangedEventId;
     case ax::mojom::Event::kFocus:
     case ax::mojom::Event::kFocusContext:
     case ax::mojom::Event::kFocusAfterMenuClose:
@@ -5582,6 +5599,11 @@ AXPlatformNodeWin::GetPatternProviderFactoryMethod(PATTERNID pattern_id) {
       }
       break;
 
+      // TODO(schectman): add implementations for ITextProvider and
+      // ITextRangeProvider interfaces.
+      // https://github.com/flutter/flutter/issues/114547 and
+      // https://github.com/flutter/flutter/issues/109804
+
     case UIA_TogglePatternId:
       if (SupportsToggle(data.role)) {
         return &PatternProvider<IToggleProvider>;
diff --git a/third_party/accessibility/ax/platform/ax_platform_node_win_unittest.cc b/third_party/accessibility/ax/platform/ax_platform_node_win_unittest.cc
index 90d5e40156d0f..bfa064a425f1f 100644
--- a/third_party/accessibility/ax/platform/ax_platform_node_win_unittest.cc
+++ b/third_party/accessibility/ax/platform/ax_platform_node_win_unittest.cc
@@ -1760,7 +1760,7 @@ TEST_F(AXPlatformNodeWinTest, ITableItemProviderGetRowHeaderItems) {
   EXPECT_EQ(nullptr, safearray.Get());
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertySimple) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertySimple) {
   AXNodeData root;
   root.role = ax::mojom::Role::kList;
   root.SetName("fake name");
@@ -1820,7 +1820,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertySimple) {
   EXPECT_UIA_INT_EQ(child_node1, UIA_PositionInSetPropertyId, 1);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueClickablePoint) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueClickablePoint) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kButton;
@@ -1837,7 +1837,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueClickablePoint) {
                              UIA_ClickablePointPropertyId, expected_values);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueIsDialog) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueIsDialog) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -1948,7 +1948,7 @@ TEST_F(AXPlatformNodeWinTest,
                      UIA_IsControlElementPropertyId, false);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetControllerForPropertyId) {
+TEST_F(AXPlatformNodeWinTest, UIAGetControllerForPropertyId) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -1996,7 +1996,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetControllerForPropertyId) {
       expected_names_2);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetDescribedByPropertyId) {
+TEST_F(AXPlatformNodeWinTest, UIAGetDescribedByPropertyId) {
   AXNodeData root;
   std::vector<AXNode::AXID> describedby_ids = {2, 3, 4};
   root.AddIntListAttribute(ax::mojom::IntListAttribute::kDescribedbyIds,
@@ -2029,7 +2029,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetDescribedByPropertyId) {
       root_node, UIA_DescribedByPropertyId, UIA_NamePropertyId, expected_names);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAItemStatusPropertyId) {
+TEST_F(AXPlatformNodeWinTest, UIAItemStatusPropertyId) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kTable;
@@ -2097,7 +2097,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAItemStatusPropertyId) {
       UIA_ItemStatusPropertyId, ScopedVariant::kEmptyVariant);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetFlowsToPropertyId) {
+TEST_F(AXPlatformNodeWinTest, UIAGetFlowsToPropertyId) {
   AXNodeData root;
   std::vector<AXNode::AXID> flowto_ids = {2, 3, 4};
   root.AddIntListAttribute(ax::mojom::IntListAttribute::kFlowtoIds, flowto_ids);
@@ -2128,7 +2128,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetFlowsToPropertyId) {
                                             UIA_NamePropertyId, expected_names);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromNone) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueFlowsFromNone) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2146,7 +2146,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromNone) {
   EXPECT_EQ(nullptr, V_ARRAY(property_value.ptr()));
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromSingle) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueFlowsFromSingle) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2171,7 +2171,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromSingle) {
       child_node1, UIA_FlowsFromPropertyId, UIA_NamePropertyId, expected_names);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromMultiple) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueFlowsFromMultiple) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2215,7 +2215,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFlowsFromMultiple) {
       expected_names_2);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetPropertyValueFrameworkId) {
+TEST_F(AXPlatformNodeWinTest, UIAGetPropertyValueFrameworkId) {
   AXNodeData root_ax_node_data;
   root_ax_node_data.id = 1;
   root_ax_node_data.role = ax::mojom::Role::kRootWebArea;
@@ -2554,7 +2554,7 @@ TEST_F(AXPlatformNodeWinTest, GetPropertyValue_IsControlElement) {
                      UIA_IsControlElementPropertyId, true);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetProviderOptions) {
+TEST_F(AXPlatformNodeWinTest, UIAGetProviderOptions) {
   AXNodeData root_data;
   root_data.id = 1;
   Init(root_data);
@@ -2571,7 +2571,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetProviderOptions) {
             provider_options);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetHostRawElementProvider) {
+TEST_F(AXPlatformNodeWinTest, UIAGetHostRawElementProvider) {
   AXNodeData root_data;
   root_data.id = 1;
   Init(root_data);
@@ -2585,7 +2585,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetHostRawElementProvider) {
   EXPECT_EQ(nullptr, host_provider.Get());
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetBoundingRectangle) {
+TEST_F(AXPlatformNodeWinTest, UIAGetBoundingRectangle) {
   AXNodeData root_data;
   root_data.id = 1;
   root_data.relative_bounds.bounds = gfx::RectF(10, 20, 30, 50);
@@ -2603,7 +2603,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetBoundingRectangle) {
   EXPECT_EQ(50, bounding_rectangle.height);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetFragmentRoot) {
+TEST_F(AXPlatformNodeWinTest, UIAGetFragmentRoot) {
   // This test needs to be run on a child node since AXPlatformRootNodeWin
   // overrides the method.
   AXNodeData root_data;
@@ -2643,7 +2643,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetFragmentRoot) {
       element1_provider->get_FragmentRoot(&actual_fragment_root));
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetEmbeddedFragmentRoots) {
+TEST_F(AXPlatformNodeWinTest, UIAGetEmbeddedFragmentRoots) {
   AXNodeData root_data;
   root_data.id = 1;
   Init(root_data);
@@ -2657,7 +2657,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetEmbeddedFragmentRoots) {
   EXPECT_EQ(nullptr, embedded_fragment_roots.Get());
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetRuntimeId) {
+TEST_F(AXPlatformNodeWinTest, UIAGetRuntimeId) {
   AXNodeData root_data;
   root_data.id = 1;
   Init(root_data);
@@ -2687,7 +2687,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAGetRuntimeId) {
   EXPECT_HRESULT_SUCCEEDED(::SafeArrayUnaccessData(runtime_id.Get()));
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalUnset) {
+TEST_F(AXPlatformNodeWinTest, UIAIWindowProviderGetIsModalUnset) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2701,7 +2701,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalUnset) {
   ASSERT_EQ(nullptr, window_provider.Get());
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalFalse) {
+TEST_F(AXPlatformNodeWinTest, UIAIWindowProviderGetIsModalFalse) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2720,7 +2720,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalFalse) {
   ASSERT_FALSE(is_modal);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalTrue) {
+TEST_F(AXPlatformNodeWinTest, UIAIWindowProviderGetIsModalTrue) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2739,7 +2739,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderGetIsModalTrue) {
   ASSERT_TRUE(is_modal);
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderInvalidArgument) {
+TEST_F(AXPlatformNodeWinTest, UIAIWindowProviderInvalidArgument) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2762,7 +2762,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderInvalidArgument) {
   ASSERT_EQ(E_INVALIDARG, window_provider->get_IsTopmost(nullptr));
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderNotSupported) {
+TEST_F(AXPlatformNodeWinTest, UIAIWindowProviderNotSupported) {
   AXNodeData root;
   root.id = 1;
   root.role = ax::mojom::Role::kRootWebArea;
@@ -2800,7 +2800,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIAIWindowProviderNotSupported) {
             window_provider->get_IsTopmost(&bool_result));
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIANavigate) {
+TEST_F(AXPlatformNodeWinTest, UIANavigate) {
   AXNodeData root_data;
   root_data.id = 1;
 
@@ -3076,7 +3076,7 @@ TEST_F(AXPlatformNodeWinTest, ComputeUIAControlType) {
       UIA_ControlTypePropertyId, int{UIA_EditControlTypeId});
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIALandmarkType) {
+TEST_F(AXPlatformNodeWinTest, UIALandmarkType) {
   auto TestLandmarkType = [this](ax::mojom::Role node_role,
                                  std::optional<LONG> expected_landmark_type,
                                  const std::string& node_name = {}) {
@@ -3120,7 +3120,7 @@ TEST_F(AXPlatformNodeWinTest, DISABLED_UIALandmarkType) {
   TestLandmarkType(ax::mojom::Role::kTable, {});
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIALocalizedLandmarkType) {
+TEST_F(AXPlatformNodeWinTest, UIALocalizedLandmarkType) {
   auto TestLocalizedLandmarkType =
       [this](ax::mojom::Role node_role,
              const std::wstring& expected_localized_landmark,
@@ -3196,7 +3196,7 @@ TEST_F(AXPlatformNodeWinTest, IRawElementProviderSimple2ShowContextMenu) {
   EXPECT_EQ(root_node, TestAXNodeWrapper::GetNodeFromLastShowContextMenu());
 }
 
-TEST_F(AXPlatformNodeWinTest, DISABLED_UIAErrorHandling) {
+TEST_F(AXPlatformNodeWinTest, UIAErrorHandling) {
   AXNodeData root;
   root.id = 1;
   Init(root);
diff --git a/third_party/accessibility/ax/platform/test_ax_node_wrapper.cc b/third_party/accessibility/ax/platform/test_ax_node_wrapper.cc
index 7270b83911da4..05a655194948e 100644
--- a/third_party/accessibility/ax/platform/test_ax_node_wrapper.cc
+++ b/third_party/accessibility/ax/platform/test_ax_node_wrapper.cc
@@ -54,9 +54,14 @@ std::map<AXNode::AXID, AXNode::AXID> g_hit_test_result;
 class TestAXTreeObserver : public AXTreeObserver {
  private:
   void OnNodeDeleted(AXTree* tree, int32_t node_id) override {
-    const auto iter = g_node_id_to_wrapper_map.find(node_id);
+    const auto& iter = g_node_id_to_wrapper_map.find(node_id);
     if (iter != g_node_id_to_wrapper_map.end()) {
       TestAXNodeWrapper* wrapper = iter->second;
+      const auto& focus_iter = g_focused_node_in_tree.find(tree);
+      if (focus_iter != g_focused_node_in_tree.end() &&
+          focus_iter->second->id() == node_id) {
+        g_focused_node_in_tree.erase(tree);
+      }
       delete wrapper;
       g_node_id_to_wrapper_map.erase(node_id);
     }