diff --git a/dwds/CHANGELOG.md b/dwds/CHANGELOG.md
index 52b5dbabe..95cd526b0 100644
--- a/dwds/CHANGELOG.md
+++ b/dwds/CHANGELOG.md
@@ -1,4 +1,5 @@
 ## 24.2.0-wip
+- Replace deprecated JS code `this.__proto__` with `Object.getPrototypeOf(this)` - [#2500](https://github.com/dart-lang/webdev/pull/2500)
 
 ## 24.1.0
 
diff --git a/dwds/lib/src/debugging/inspector.dart b/dwds/lib/src/debugging/inspector.dart
index 4bde89f75..c13dcf27d 100644
--- a/dwds/lib/src/debugging/inspector.dart
+++ b/dwds/lib/src/debugging/inspector.dart
@@ -215,7 +215,7 @@ class AppInspector implements AppInspectorInterface {
     // We use the JS pseudo-variable 'arguments' to get the list of all arguments.
     final send = '''
         function () {
-          if (!(this.__proto__)) { return 'Instance of PlainJavaScriptObject';}
+          if (!Object.getPrototypeOf(this)) { return 'Instance of PlainJavaScriptObject';}
           return ${globalToolConfiguration.loadStrategy.loadModuleSnippet}("dart_sdk").dart.dsendRepl(this, "$methodName", arguments);
         }
         ''';