diff --git a/pkgs/dartpad_ui/lib/embed.dart b/pkgs/dartpad_ui/lib/embed.dart
index 97736d3a7..129b9f05c 100644
--- a/pkgs/dartpad_ui/lib/embed.dart
+++ b/pkgs/dartpad_ui/lib/embed.dart
@@ -11,7 +11,7 @@ import 'model.dart';
 /// Listen to frame messages if embedded as an iFrame
 /// to accept injected snippets.
 void handleEmbedMessage(AppServices services, {bool runOnInject = false}) {
-  final parent = web.window.parent;
+  final parent = web.window.parentCrossOrigin;
   if (parent == null) return;
 
   web.window.addEventListener(
diff --git a/pkgs/dartpad_ui/lib/execution/frame.dart b/pkgs/dartpad_ui/lib/execution/frame.dart
index 795f96c9e..71b30573c 100644
--- a/pkgs/dartpad_ui/lib/execution/frame.dart
+++ b/pkgs/dartpad_ui/lib/execution/frame.dart
@@ -9,7 +9,6 @@ import 'dart:js_interop';
 import 'package:web/web.dart' as web;
 
 import '../model.dart';
-import 'frame_utils.dart';
 
 class ExecutionServiceImpl implements ExecutionService {
   final StreamController<String> _stdoutController =
@@ -134,12 +133,14 @@ require(["dartpad_main", "dart_sdk"], function(dartpad_main, dart_sdk) {
   }
 
   Future<void> _send(String command, Map<String, Object?> params) {
-    final message = {
-      'command': command,
-      ...params,
-    }.jsify();
     // TODO: Use dartpad.dev instead of '*'?
-    _frame.safelyPostMessage(message, '*');
+    _frame.contentWindowCrossOrigin?.postMessage(
+      {
+        'command': command,
+        ...params,
+      }.jsify(),
+      '*'.toJS,
+    );
     return Future.value();
   }
 
diff --git a/pkgs/dartpad_ui/lib/execution/frame_utils.dart b/pkgs/dartpad_ui/lib/execution/frame_utils.dart
deleted file mode 100644
index 969bcb4b5..000000000
--- a/pkgs/dartpad_ui/lib/execution/frame_utils.dart
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'dart:js_interop';
-import 'dart:js_interop_unsafe';
-
-import 'package:web/web.dart';
-
-/// Extensions to work around Dart compiler issues that result in calls that
-/// sandboxed iframes error on.
-///
-/// If the compilers are adjusted to handle this case or `package:web` provides
-/// a helper for this, switch to that.
-///
-/// Tracked in https://github.com/dart-lang/sdk/issues/54443.
-extension HTMLIFrameElementExtension on HTMLIFrameElement {
-  /// Send the specified [message] to this iframe, configured with the specified
-  /// [optionsOrTargetOrigin].
-  void safelyPostMessage(
-    JSAny? message,
-    String optionsOrTargetOrigin,
-  ) {
-    // Uses unsafe calls to prevent the Dart web compilers from
-    // inserting type or null checks that access restricted properties.
-    (this as JSObject)
-        .getProperty<JSObject>('contentWindow'.toJS)
-        .callMethod('postMessage'.toJS, message, optionsOrTargetOrigin.toJS);
-  }
-}
diff --git a/pkgs/dartpad_ui/pubspec.yaml b/pkgs/dartpad_ui/pubspec.yaml
index 1ed61446c..563e01c55 100644
--- a/pkgs/dartpad_ui/pubspec.yaml
+++ b/pkgs/dartpad_ui/pubspec.yaml
@@ -22,7 +22,7 @@ dependencies:
   split_view: ^3.2.1
   url_launcher: ^6.3.0
   vtable: ^0.4.0
-  web: ^1.0.0
+  web: ^1.1.0
 
 dev_dependencies:
   flutter_test: