diff --git a/apps/ai-game-creator-shell/src/features/ui-editor/useUiEditorState.ts b/apps/ai-game-creator-shell/src/features/ui-editor/useUiEditorState.ts
index 13ffa45e8..36c49730b 100644
--- a/apps/ai-game-creator-shell/src/features/ui-editor/useUiEditorState.ts
+++ b/apps/ai-game-creator-shell/src/features/ui-editor/useUiEditorState.ts
@@ -237,7 +237,30 @@ function cloneState(state: State): State {
 }
 
 function sameResource<T>(left: T, right: T): boolean {
-  return JSON.stringify(left) === JSON.stringify(right);
+  if (Object.is(left, right)) return true;
+  if (
+    typeof left !== 'object' ||
+    left === null ||
+    typeof right !== 'object' ||
+    right === null
+  ) {
+    return false;
+  }
+  if (Array.isArray(left) || Array.isArray(right)) {
+    if (!Array.isArray(left) || !Array.isArray(right)) return false;
+    if (left.length !== right.length) return false;
+    return left.every((value, index) => sameResource(value, right[index]));
+  }
+  const leftRecord = left as Record<string, unknown>;
+  const rightRecord = right as Record<string, unknown>;
+  const leftKeys = Object.keys(leftRecord);
+  const rightKeys = Object.keys(rightRecord);
+  if (leftKeys.length !== rightKeys.length) return false;
+  return leftKeys.every(
+    (key) =>
+      Object.prototype.hasOwnProperty.call(rightRecord, key) &&
+      sameResource(leftRecord[key], rightRecord[key]),
+  );
 }
 
 function visitComponents(nodes: Node[], visit: (component: Component) => void) {
@@ -540,7 +563,7 @@ export function useUiEditorState(initialState: State = EMPTY_UI_EDITOR_STATE) {
   const commit = useCallback(
     (nextState: State) => {
       const current = stateRef.current;
-      if (JSON.stringify(current) === JSON.stringify(nextState)) return false;
+      if (sameResource(current, nextState)) return false;
       if (transactionRef.current === null) {
         undoStackRef.current.push({
           before: cloneState(current),
@@ -576,7 +599,7 @@ export function useUiEditorState(initialState: State = EMPTY_UI_EDITOR_STATE) {
     if (transaction === null) return;
     transactionRef.current = null;
     const current = stateRef.current;
-    if (JSON.stringify(transaction.before) === JSON.stringify(current)) {
+    if (sameResource(transaction.before, current)) {
       return;
     }
     undoStackRef.current.push({