diff --git a/ci/licenses_golden/licenses_flutter b/ci/licenses_golden/licenses_flutter
index f02a1846afa9f..8f5f1cee157ca 100644
--- a/ci/licenses_golden/licenses_flutter
+++ b/ci/licenses_golden/licenses_flutter
@@ -2146,6 +2146,7 @@ ORIGIN: ../../../flutter/lib/web_ui/lib/ui.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/asset_manager.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/benchmarks.dart + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/images.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/initialization.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/navigation/platform_location.dart + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/navigation/url_strategy.dart + ../../../flutter/LICENSE
@@ -4878,6 +4879,7 @@ FILE: ../../../flutter/lib/web_ui/lib/ui.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/asset_manager.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/benchmarks.dart
+FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/images.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/initialization.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/navigation/platform_location.dart
 FILE: ../../../flutter/lib/web_ui/lib/ui_web/src/ui_web/navigation/url_strategy.dart
diff --git a/lib/web_ui/lib/initialization.dart b/lib/web_ui/lib/initialization.dart
index f3f0208a0981a..9e1641186b3df 100644
--- a/lib/web_ui/lib/initialization.dart
+++ b/lib/web_ui/lib/initialization.dart
@@ -31,6 +31,13 @@ part of ui;
 // TODO(mdebbar): Deprecate this and remove it.
 // https://github.com/flutter/flutter/issues/127395
 Future<void> webOnlyInitializePlatform() async {
+  assert(() {
+    engine.printWarning(
+      'The webOnlyInitializePlatform API is deprecated and will be removed in a '
+      'future release. Please use `bootstrapEngine` from `dart:ui_web` instead.',
+    );
+    return true;
+  }());
   await engine.initializeEngine();
 }
 
diff --git a/lib/web_ui/lib/painting.dart b/lib/web_ui/lib/painting.dart
index b974b4868968d..24261b30e03a1 100644
--- a/lib/web_ui/lib/painting.dart
+++ b/lib/web_ui/lib/painting.dart
@@ -533,9 +533,22 @@ class TargetImageSize {
   final int? height;
 }
 
-Future<Codec> webOnlyInstantiateImageCodecFromUrl(Uri uri,
-  {engine.WebOnlyImageCodecChunkCallback? chunkCallback}) =>
-  engine.renderer.instantiateImageCodecFromUrl(uri, chunkCallback: chunkCallback);
+// TODO(mdebbar): Deprecate this and remove it.
+// https://github.com/flutter/flutter/issues/127395
+Future<Codec> webOnlyInstantiateImageCodecFromUrl(
+  Uri uri, {
+  ui_web.ImageCodecChunkCallback? chunkCallback,
+}) {
+  assert(() {
+    engine.printWarning(
+      'The webOnlyInstantiateImageCodecFromUrl API is deprecated and will be '
+      'removed in a future release. Please use `createImageCodecFromUrl` from '
+      '`dart:ui_web` instead.',
+    );
+    return true;
+  }());
+  return ui_web.createImageCodecFromUrl(uri, chunkCallback: chunkCallback);
+}
 
 void decodeImageFromList(Uint8List list, ImageDecoderCallback callback) {
   _decodeImageFromListAsync(list, callback);
diff --git a/lib/web_ui/lib/src/engine/canvaskit/image.dart b/lib/web_ui/lib/src/engine/canvaskit/image.dart
index 11af8b8a3d59b..fd822860c1d0f 100644
--- a/lib/web_ui/lib/src/engine/canvaskit/image.dart
+++ b/lib/web_ui/lib/src/engine/canvaskit/image.dart
@@ -8,6 +8,7 @@ import 'dart:typed_data';
 
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 /// Instantiates a [ui.Codec] backed by an `SkAnimatedImage` from Skia.
 FutureOr<ui.Codec> skiaInstantiateImageCodec(Uint8List list,
@@ -159,7 +160,7 @@ const String _kNetworkImageMessage = 'Failed to load network image.';
 /// Instantiates a [ui.Codec] backed by an `SkAnimatedImage` from Skia after
 /// requesting from URI.
 Future<ui.Codec> skiaInstantiateWebImageCodec(
-    String url, WebOnlyImageCodecChunkCallback? chunkCallback) async {
+    String url, ui_web.ImageCodecChunkCallback? chunkCallback) async {
   final Uint8List list = await fetchImage(url, chunkCallback);
   if (browserSupportsImageDecoder) {
     return CkBrowserImageDecoder.create(data: list, debugSource: url);
@@ -169,7 +170,7 @@ Future<ui.Codec> skiaInstantiateWebImageCodec(
 }
 
 /// Sends a request to fetch image data.
-Future<Uint8List> fetchImage(String url, WebOnlyImageCodecChunkCallback? chunkCallback) async {
+Future<Uint8List> fetchImage(String url, ui_web.ImageCodecChunkCallback? chunkCallback) async {
   try {
     final HttpFetchResponse response = await httpFetch(url);
     final int? contentLength = response.contentLength;
@@ -200,7 +201,7 @@ Future<Uint8List> fetchImage(String url, WebOnlyImageCodecChunkCallback? chunkCa
 /// Reads the [payload] in chunks using the browser's Streams API
 ///
 /// See: https://developer.mozilla.org/en-US/docs/Web/API/Streams_API
-Future<Uint8List> readChunked(HttpFetchPayload payload, int contentLength, WebOnlyImageCodecChunkCallback chunkCallback) async {
+Future<Uint8List> readChunked(HttpFetchPayload payload, int contentLength, ui_web.ImageCodecChunkCallback chunkCallback) async {
   final JSUint8Array result = createUint8ArrayFromLength(contentLength);
   int position = 0;
   int cumulativeBytesLoaded = 0;
diff --git a/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart b/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
index 9048c857a584b..d6f732e9bae24 100644
--- a/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
+++ b/lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart
@@ -81,7 +81,6 @@ class LayerSceneBuilder implements ui.SceneBuilder {
     ui.Offset offset = ui.Offset.zero,
     double width = 0.0,
     double height = 0.0,
-    Object? webOnlyPaintedBy,
   }) {
     currentLayer.add(PlatformViewLayer(viewId, offset, width, height));
   }
diff --git a/lib/web_ui/lib/src/engine/canvaskit/renderer.dart b/lib/web_ui/lib/src/engine/canvaskit/renderer.dart
index 96da491f69af4..b94f75047e607 100644
--- a/lib/web_ui/lib/src/engine/canvaskit/renderer.dart
+++ b/lib/web_ui/lib/src/engine/canvaskit/renderer.dart
@@ -209,7 +209,7 @@ class CanvasKitRenderer implements Renderer {
   @override
   Future<ui.Codec> instantiateImageCodecFromUrl(
     Uri uri, {
-    WebOnlyImageCodecChunkCallback? chunkCallback
+    ui_web.ImageCodecChunkCallback? chunkCallback
   }) => skiaInstantiateWebImageCodec(uri.toString(), chunkCallback);
 
   @override
diff --git a/lib/web_ui/lib/src/engine/html/renderer.dart b/lib/web_ui/lib/src/engine/html/renderer.dart
index 728c8bc367ce2..5084a202d4de0 100644
--- a/lib/web_ui/lib/src/engine/html/renderer.dart
+++ b/lib/web_ui/lib/src/engine/html/renderer.dart
@@ -8,6 +8,7 @@ import 'dart:typed_data';
 
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 class HtmlRenderer implements Renderer {
   static HtmlRenderer get instance => _instance;
@@ -176,11 +177,9 @@ class HtmlRenderer implements Renderer {
   @override
   Future<ui.Codec> instantiateImageCodecFromUrl(
     Uri uri, {
-    WebOnlyImageCodecChunkCallback? chunkCallback}) {
-      return futurize<ui.Codec>((Callback<ui.Codec> callback) {
-        callback(HtmlCodec(uri.toString(), chunkCallback: chunkCallback));
-        return null;
-      });
+    ui_web.ImageCodecChunkCallback? chunkCallback,
+  }) async {
+    return HtmlCodec(uri.toString(), chunkCallback: chunkCallback);
   }
 
   @override
diff --git a/lib/web_ui/lib/src/engine/html/scene_builder.dart b/lib/web_ui/lib/src/engine/html/scene_builder.dart
index e77e7d47928f9..5f1a7c687474c 100644
--- a/lib/web_ui/lib/src/engine/html/scene_builder.dart
+++ b/lib/web_ui/lib/src/engine/html/scene_builder.dart
@@ -329,7 +329,7 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// overlay or not.
   ///
   /// We use this to avoid spamming the console with redundant warning messages.
-  static bool _webOnlyDidWarnAboutPerformanceOverlay = false;
+  static bool _didWarnAboutPerformanceOverlay = false;
 
   void _addPerformanceOverlay(
     int enabledOptions,
@@ -338,8 +338,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
     double top,
     double bottom,
   ) {
-    if (!_webOnlyDidWarnAboutPerformanceOverlay) {
-      _webOnlyDidWarnAboutPerformanceOverlay = true;
+    if (!_didWarnAboutPerformanceOverlay) {
+      _didWarnAboutPerformanceOverlay = true;
       printWarning("The performance overlay isn't supported on the web");
     }
   }
diff --git a/lib/web_ui/lib/src/engine/html_image_codec.dart b/lib/web_ui/lib/src/engine/html_image_codec.dart
index 5c7935816cb58..e5cdad6b7b309 100644
--- a/lib/web_ui/lib/src/engine/html_image_codec.dart
+++ b/lib/web_ui/lib/src/engine/html_image_codec.dart
@@ -6,6 +6,7 @@ import 'dart:async';
 import 'dart:typed_data';
 
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 import 'browser_detection.dart';
 import 'dom.dart';
@@ -20,14 +21,15 @@ Object? get _jsImageDecodeFunction => getJsProperty<Object?>(
 );
 final bool _supportsDecode = _jsImageDecodeFunction != null;
 
-typedef WebOnlyImageCodecChunkCallback = void Function(
-    int cumulativeBytesLoaded, int expectedTotalBytes);
+// TODO(mdebbar): Deprecate this and remove it.
+// https://github.com/flutter/flutter/issues/127395
+typedef WebOnlyImageCodecChunkCallback = ui_web.ImageCodecChunkCallback;
 
 class HtmlCodec implements ui.Codec {
   HtmlCodec(this.src, {this.chunkCallback});
 
   final String src;
-  final WebOnlyImageCodecChunkCallback? chunkCallback;
+  final ui_web.ImageCodecChunkCallback? chunkCallback;
 
   @override
   int get frameCount => 1;
diff --git a/lib/web_ui/lib/src/engine/renderer.dart b/lib/web_ui/lib/src/engine/renderer.dart
index 20fd055b1c13d..c6a84ab959600 100644
--- a/lib/web_ui/lib/src/engine/renderer.dart
+++ b/lib/web_ui/lib/src/engine/renderer.dart
@@ -8,6 +8,7 @@ import 'dart:typed_data';
 
 import 'package:ui/src/engine/skwasm/skwasm_stub.dart' if (dart.library.ffi) 'package:ui/src/engine/skwasm/skwasm_impl.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 import 'browser_detection.dart';
 import 'canvaskit/renderer.dart';
@@ -15,7 +16,6 @@ import 'configuration.dart';
 import 'embedder.dart';
 import 'fonts.dart';
 import 'html/renderer.dart';
-import 'html_image_codec.dart';
 
 final Renderer _renderer = Renderer._internal();
 Renderer get renderer => _renderer;
@@ -131,7 +131,7 @@ abstract class Renderer {
 
   Future<ui.Codec> instantiateImageCodecFromUrl(
     Uri uri, {
-    WebOnlyImageCodecChunkCallback? chunkCallback,
+    ui_web.ImageCodecChunkCallback? chunkCallback,
   });
 
   void decodeImageFromPixels(
diff --git a/lib/web_ui/lib/src/engine/skwasm/skwasm_impl/renderer.dart b/lib/web_ui/lib/src/engine/skwasm/skwasm_impl/renderer.dart
index 71fc79ad335a9..08c86b269458e 100644
--- a/lib/web_ui/lib/src/engine/skwasm/skwasm_impl/renderer.dart
+++ b/lib/web_ui/lib/src/engine/skwasm/skwasm_impl/renderer.dart
@@ -389,7 +389,7 @@ class SkwasmRenderer implements Renderer {
   @override
   Future<ui.Codec> instantiateImageCodecFromUrl(
     Uri uri, {
-    WebOnlyImageCodecChunkCallback? chunkCallback
+    ui_web.ImageCodecChunkCallback? chunkCallback
   }) async {
     final DomResponse response = await rawHttpGet(uri.toString());
     final String? contentType = response.headers.get('Content-Type');
diff --git a/lib/web_ui/lib/src/engine/skwasm/skwasm_stub/renderer.dart b/lib/web_ui/lib/src/engine/skwasm/skwasm_stub/renderer.dart
index 3d4823f49cc2c..314cf0b616f95 100644
--- a/lib/web_ui/lib/src/engine/skwasm/skwasm_stub/renderer.dart
+++ b/lib/web_ui/lib/src/engine/skwasm/skwasm_stub/renderer.dart
@@ -145,7 +145,7 @@ class SkwasmRenderer implements Renderer {
   }
 
   @override
-  Future<ui.Codec> instantiateImageCodecFromUrl(Uri uri, {WebOnlyImageCodecChunkCallback? chunkCallback}) {
+  Future<ui.Codec> instantiateImageCodecFromUrl(Uri uri, {ui_web.ImageCodecChunkCallback? chunkCallback}) {
     throw UnimplementedError('Skwasm not implemented on this platform.');
   }
 
diff --git a/lib/web_ui/lib/src/engine/window.dart b/lib/web_ui/lib/src/engine/window.dart
index 707be6b38ee76..834027100e32a 100644
--- a/lib/web_ui/lib/src/engine/window.dart
+++ b/lib/web_ui/lib/src/engine/window.dart
@@ -255,8 +255,8 @@ class EngineFlutterWindow extends ui.SingletonFlutterWindow {
     bool override = false;
 
     assert(() {
-      if (webOnlyDebugPhysicalSizeOverride != null) {
-        _physicalSize = webOnlyDebugPhysicalSizeOverride;
+      if (debugPhysicalSizeOverride != null) {
+        _physicalSize = debugPhysicalSizeOverride;
         override = true;
       }
       return true;
@@ -319,8 +319,37 @@ class EngineFlutterWindow extends ui.SingletonFlutterWindow {
   /// Lazily populated and cleared at the end of the frame.
   ui.Size? _physicalSize;
 
-  /// Overrides the value of [physicalSize] in tests.
-  ui.Size? webOnlyDebugPhysicalSizeOverride;
+  // TODO(mdebbar): Deprecate this and remove it.
+  // https://github.com/flutter/flutter/issues/127395
+  ui.Size? get webOnlyDebugPhysicalSizeOverride {
+    assert(() {
+      printWarning(
+        'The webOnlyDebugPhysicalSizeOverride API is deprecated and will be '
+        'removed in a future release. Please use '
+        '`SingletonFlutterWindow.debugPhysicalSizeOverride` from `dart:ui_web` '
+        'instead.',
+      );
+      return true;
+    }());
+    return debugPhysicalSizeOverride;
+  }
+
+  // TODO(mdebbar): Deprecate this and remove it.
+  // https://github.com/flutter/flutter/issues/127395
+  set webOnlyDebugPhysicalSizeOverride(ui.Size? value) {
+    assert(() {
+      printWarning(
+        'The webOnlyDebugPhysicalSizeOverride API is deprecated and will be '
+        'removed in a future release. Please use '
+        '`SingletonFlutterWindow.debugPhysicalSizeOverride` from `dart:ui_web` '
+        'instead.',
+      );
+      return true;
+    }());
+    debugPhysicalSizeOverride = value;
+  }
+
+  ui.Size? debugPhysicalSizeOverride;
 }
 
 /// The Web implementation of [ui.SingletonFlutterWindow].
@@ -336,7 +365,7 @@ class EngineSingletonFlutterWindow extends EngineFlutterWindow {
   /// Overrides the default device pixel ratio.
   ///
   /// This is useful in tests to emulate screens of different dimensions.
-  void debugOverrideDevicePixelRatio(double value) {
+  void debugOverrideDevicePixelRatio(double? value) {
     _debugDevicePixelRatio = value;
   }
 
diff --git a/lib/web_ui/lib/ui_web/src/ui_web.dart b/lib/web_ui/lib/ui_web/src/ui_web.dart
index 02ec39b539595..3d4a9262d60c4 100644
--- a/lib/web_ui/lib/ui_web/src/ui_web.dart
+++ b/lib/web_ui/lib/ui_web/src/ui_web.dart
@@ -10,6 +10,7 @@ library ui_web;
 
 export 'ui_web/asset_manager.dart';
 export 'ui_web/benchmarks.dart';
+export 'ui_web/images.dart';
 export 'ui_web/initialization.dart';
 export 'ui_web/navigation/platform_location.dart';
 export 'ui_web/navigation/url_strategy.dart';
diff --git a/lib/web_ui/lib/ui_web/src/ui_web/images.dart b/lib/web_ui/lib/ui_web/src/ui_web/images.dart
new file mode 100644
index 0000000000000..d8e4de718111d
--- /dev/null
+++ b/lib/web_ui/lib/ui_web/src/ui_web/images.dart
@@ -0,0 +1,27 @@
+// 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.
+
+import 'package:ui/src/engine.dart';
+import 'package:ui/ui.dart' as ui;
+
+/// Signature of the callback that receives progress updates as image chunks are
+/// loaded.
+typedef ImageCodecChunkCallback = void Function(
+  int cumulativeBytesLoaded,
+  int expectedTotalBytes,
+);
+
+/// Creates a [ui.Codec] for the image located at [uri].
+///
+/// The [chunkCallback] is called with progress updates as image chunks are
+/// loaded.
+Future<ui.Codec> createImageCodecFromUrl(
+  Uri uri, {
+  ImageCodecChunkCallback? chunkCallback,
+}) {
+  return renderer.instantiateImageCodecFromUrl(
+    uri,
+    chunkCallback: chunkCallback,
+  );
+}
diff --git a/lib/web_ui/lib/ui_web/src/ui_web/testing.dart b/lib/web_ui/lib/ui_web/src/ui_web/testing.dart
index ae5b6e88e34e7..5af1694a3aba4 100644
--- a/lib/web_ui/lib/ui_web/src/ui_web/testing.dart
+++ b/lib/web_ui/lib/ui_web/src/ui_web/testing.dart
@@ -5,6 +5,18 @@
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
 
+extension SingletonFlutterWindowExtension on ui.SingletonFlutterWindow {
+  /// Overrides the value of [physicalSize] in tests.
+  set debugPhysicalSizeOverride(ui.Size? value) {
+    (this as EngineFlutterWindow).debugPhysicalSizeOverride = value;
+  }
+}
+
+/// Overrides the value of [ui.FlutterView.devicePixelRatio] in tests.
+void debugOverrideDevicePixelRatio(double? value) {
+  (ui.window as EngineSingletonFlutterWindow).debugOverrideDevicePixelRatio(value);
+}
+
 /// Whether the Flutter engine is running in `flutter test` emulation mode.
 ///
 /// When true, the engine will emulate a specific screen size, and always
@@ -18,8 +30,7 @@ set debugEmulateFlutterTesterEnvironment(bool value) {
   _debugEmulateFlutterTesterEnvironment = value;
   if (_debugEmulateFlutterTesterEnvironment) {
     const ui.Size logicalSize = ui.Size(800.0, 600.0);
-    window.webOnlyDebugPhysicalSizeOverride =
-        logicalSize * window.devicePixelRatio;
+    window.debugPhysicalSizeOverride = logicalSize * window.devicePixelRatio;
   }
   debugDisableFontFallbacks = value;
 }
diff --git a/lib/web_ui/test/canvaskit/embedded_views_test.dart b/lib/web_ui/test/canvaskit/embedded_views_test.dart
index 1187f02e5e19e..58b34661fcb4d 100644
--- a/lib/web_ui/test/canvaskit/embedded_views_test.dart
+++ b/lib/web_ui/test/canvaskit/embedded_views_test.dart
@@ -644,7 +644,7 @@ void testMain() {
       sb.addPicture(ui.Offset.zero, picture);
       sb.addPlatformView(0, width: 10, height: 10);
 
-      window.webOnlyDebugPhysicalSizeOverride = const ui.Size(100, 100);
+      window.debugPhysicalSizeOverride = const ui.Size(100, 100);
       window.debugForceResize();
       CanvasKitRenderer.instance.rasterizer.draw(sb.build().layerTree);
       _expectSceneMatches(<_EmbeddedViewMarker>[
@@ -653,7 +653,7 @@ void testMain() {
         _overlay,
       ]);
 
-      window.webOnlyDebugPhysicalSizeOverride = const ui.Size(200, 200);
+      window.debugPhysicalSizeOverride = const ui.Size(200, 200);
       window.debugForceResize();
       CanvasKitRenderer.instance.rasterizer.draw(sb.build().layerTree);
       _expectSceneMatches(<_EmbeddedViewMarker>[
@@ -662,7 +662,7 @@ void testMain() {
         _overlay,
       ]);
 
-      window.webOnlyDebugPhysicalSizeOverride = null;
+      window.debugPhysicalSizeOverride = null;
       window.debugForceResize();
     // ImageDecoder is not supported in Safari or Firefox.
     }, skip: isSafari || isFirefox);
diff --git a/lib/web_ui/test/canvaskit/fragment_program_test.dart b/lib/web_ui/test/canvaskit/fragment_program_test.dart
index f9c00901e98a1..e7eaf228f8402 100644
--- a/lib/web_ui/test/canvaskit/fragment_program_test.dart
+++ b/lib/web_ui/test/canvaskit/fragment_program_test.dart
@@ -10,6 +10,7 @@ import 'package:test/test.dart';
 
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 void main() {
   internalBootstrapBrowserTest(() => testMain);
@@ -182,7 +183,7 @@ const String kJsonIPLR = r'''
 
 void testMain() {
   setUpAll(() async {
-    await ui.webOnlyInitializePlatform();
+    await ui_web.bootstrapEngine();
   });
 
   test('FragmentProgram can be created from JSON IPLR bundle', () {
diff --git a/lib/web_ui/test/canvaskit/scene_test.dart b/lib/web_ui/test/canvaskit/scene_test.dart
index 9395c067bb3d7..4bad3c70c1da6 100644
--- a/lib/web_ui/test/canvaskit/scene_test.dart
+++ b/lib/web_ui/test/canvaskit/scene_test.dart
@@ -7,6 +7,7 @@ import 'package:test/test.dart';
 
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 void main() {
   internalBootstrapBrowserTest(() => testMain);
@@ -15,7 +16,7 @@ void main() {
 void testMain() {
   group('$LayerScene', () {
     setUpAll(() async {
-      await ui.webOnlyInitializePlatform();
+      await ui_web.bootstrapEngine();
     });
 
     test('toImage returns an image', () async {
diff --git a/lib/web_ui/test/common/test_initialization.dart b/lib/web_ui/test/common/test_initialization.dart
index 38420e1489bcd..a7714f0230774 100644
--- a/lib/web_ui/test/common/test_initialization.dart
+++ b/lib/web_ui/test/common/test_initialization.dart
@@ -32,7 +32,7 @@ void setUpUnitTests({
       // this stuff in.
       const double devicePixelRatio = 3.0;
       engine.window.debugOverrideDevicePixelRatio(devicePixelRatio);
-      engine.window.webOnlyDebugPhysicalSizeOverride =
+      engine.window.debugPhysicalSizeOverride =
           const ui.Size(800 * devicePixelRatio, 600 * devicePixelRatio);
       engine.scheduleFrameCallback = () {};
     }
diff --git a/lib/web_ui/test/engine/dom_http_fetch_test.dart b/lib/web_ui/test/engine/dom_http_fetch_test.dart
index 2433d67058cb6..48ed06a7666e5 100644
--- a/lib/web_ui/test/engine/dom_http_fetch_test.dart
+++ b/lib/web_ui/test/engine/dom_http_fetch_test.dart
@@ -8,14 +8,14 @@ import 'dart:typed_data';
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
-import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 void main() {
   internalBootstrapBrowserTest(() => testMain);
 }
 
 Future<void> testMain() async {
-  await ui.webOnlyInitializePlatform();
+  await ui_web.bootstrapEngine();
 
   // Test successful HTTP roundtrips where the server returns a happy status
   // code and a payload.
diff --git a/lib/web_ui/test/engine/image/html_image_codec_test.dart b/lib/web_ui/test/engine/image/html_image_codec_test.dart
index 1e0381ee0ec5f..e161cea5fb25e 100644
--- a/lib/web_ui/test/engine/image/html_image_codec_test.dart
+++ b/lib/web_ui/test/engine/image/html_image_codec_test.dart
@@ -9,6 +9,7 @@ import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine/html_image_codec.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 import '../../common/test_initialization.dart';
 
@@ -104,7 +105,7 @@ Future<void> testMain() async {
   group('ImageCodecUrl', () {
     test('loads sample image from web', () async {
       final Uri uri = Uri.base.resolve('sample_image1.png');
-      final HtmlCodec codec = await ui.webOnlyInstantiateImageCodecFromUrl(uri) as HtmlCodec;
+      final HtmlCodec codec = await ui_web.createImageCodecFromUrl(uri) as HtmlCodec;
       final ui.FrameInfo frameInfo = await codec.getNextFrame();
       expect(frameInfo.image, isNotNull);
       expect(frameInfo.image.width, 100);
@@ -112,7 +113,7 @@ Future<void> testMain() async {
     test('provides image loading progress from web', () async {
       final Uri uri = Uri.base.resolve('sample_image1.png');
       final StringBuffer buffer = StringBuffer();
-      final HtmlCodec codec = await ui.webOnlyInstantiateImageCodecFromUrl(uri,
+      final HtmlCodec codec = await ui_web.createImageCodecFromUrl(uri,
           chunkCallback: (int loaded, int total) {
         buffer.write('$loaded/$total,');
       }) as HtmlCodec;
diff --git a/lib/web_ui/test/engine/semantics/semantics_test.dart b/lib/web_ui/test/engine/semantics/semantics_test.dart
index 84ab72b21ca74..e5f652ea623ad 100644
--- a/lib/web_ui/test/engine/semantics/semantics_test.dart
+++ b/lib/web_ui/test/engine/semantics/semantics_test.dart
@@ -29,7 +29,7 @@ void main() {
 }
 
 Future<void> testMain() async {
-  await ui.webOnlyInitializePlatform();
+  await ui_web.bootstrapEngine();
   runSemanticsTests();
 }
 
diff --git a/lib/web_ui/test/engine/surface/platform_view_test.dart b/lib/web_ui/test/engine/surface/platform_view_test.dart
index e03b3d6a16ea1..34758cb46b7a5 100644
--- a/lib/web_ui/test/engine/surface/platform_view_test.dart
+++ b/lib/web_ui/test/engine/surface/platform_view_test.dart
@@ -20,7 +20,7 @@ void main() {
 }
 
 Future<void> testMain() async {
-  await ui.webOnlyInitializePlatform();
+  await ui_web.bootstrapEngine();
 
   late PersistedPlatformView view;
 
diff --git a/lib/web_ui/test/engine/surface/scene_builder_test.dart b/lib/web_ui/test/engine/surface/scene_builder_test.dart
index 375a5887a6052..2469e81649858 100644
--- a/lib/web_ui/test/engine/surface/scene_builder_test.dart
+++ b/lib/web_ui/test/engine/surface/scene_builder_test.dart
@@ -13,6 +13,7 @@ import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 import '../../common/matchers.dart';
 
@@ -22,7 +23,7 @@ void main() {
 
 void testMain() {
   setUpAll(() async {
-    await ui.webOnlyInitializePlatform();
+    await ui_web.bootstrapEngine();
   });
 
   group('SceneBuilder', () {
diff --git a/lib/web_ui/test/engine/surface/shaders/shader_builder_test.dart b/lib/web_ui/test/engine/surface/shaders/shader_builder_test.dart
index add593d18d5d4..02ddbfafb2e94 100644
--- a/lib/web_ui/test/engine/surface/shaders/shader_builder_test.dart
+++ b/lib/web_ui/test/engine/surface/shaders/shader_builder_test.dart
@@ -5,7 +5,7 @@
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
-import 'package:ui/ui.dart' hide window;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 void main() {
   internalBootstrapBrowserTest(() => testMain);
@@ -24,7 +24,7 @@ void testMain() {
       ')';
 
   setUpAll(() async {
-    await webOnlyInitializePlatform();
+    await ui_web.bootstrapEngine();
   });
 
   group('Shader Declarations', () {
diff --git a/lib/web_ui/test/engine/surface/surface_test.dart b/lib/web_ui/test/engine/surface/surface_test.dart
index ac807c8656370..0b43c7911eeaf 100644
--- a/lib/web_ui/test/engine/surface/surface_test.dart
+++ b/lib/web_ui/test/engine/surface/surface_test.dart
@@ -6,6 +6,7 @@ import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart';
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 void main() {
   internalBootstrapBrowserTest(() => testMain);
@@ -14,7 +15,7 @@ void main() {
 void testMain() {
   group('Surface', () {
     setUpAll(() async {
-      await webOnlyInitializePlatform();
+      await ui_web.bootstrapEngine();
     });
 
     setUp(() {
diff --git a/lib/web_ui/test/engine/window_test.dart b/lib/web_ui/test/engine/window_test.dart
index 9c957f8c9b048..85f40e1662c3a 100644
--- a/lib/web_ui/test/engine/window_test.dart
+++ b/lib/web_ui/test/engine/window_test.dart
@@ -10,6 +10,7 @@ import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';
 import 'package:ui/src/engine.dart';
 import 'package:ui/ui.dart' as ui;
+import 'package:ui/ui_web/src/ui_web.dart' as ui_web;
 
 const int kPhysicalKeyA = 0x00070004;
 const int kLogicalKeyA = 0x00000000061;
@@ -19,7 +20,7 @@ void main() {
 }
 
 Future<void> testMain() async {
-  await ui.webOnlyInitializePlatform();
+  await ui_web.bootstrapEngine();
 
   test('onTextScaleFactorChanged preserves the zone', () {
     final Zone innerZone = Zone.current.fork();