chromium/content/test/data/accessibility/event/aria-hidden-single-descendant-display-none.html

<!--
@WIN-DENY:IA2_EVENT_TEXT_INSERTED*
@WIN-DENY:IA2_EVENT_TEXT_REMOVED*
@WIN-DENY:EVENT_OBJECT_REORDER*
@UIA-WIN-DENY:StructureChanged/ChildrenReordered*
-->
<html>
<body>
  <div style="display: none">
    <div class="test-case" aria-hidden="false">
      <button>expect invisible subtree</button>
    </div>
    <div class="test-case" aria-hidden="true">
      <button>expect invisible subtree</button>
    </div>
  </div>
  <script>
    var current_pass = 0;
    var test_cases = document.querySelectorAll('.test-case[aria-hidden]');

    function run_test_case(element) {
      let hidden = element.getAttribute('aria-hidden') == 'true';
      element.setAttribute('aria-hidden', !hidden);
    }

    function go() {
      run_test_case(test_cases.item(current_pass++));
      return current_pass < test_cases.length;
    }
  </script>
</body>
</html>