chromium/content/test/data/accessibility/html/fencedframe-scrollable-mparch.html

<!--
@BLINK-ALLOW:scrollable=*
-->
<!DOCTYPE html>
<html style="width:100px; height:100px;">
<body>
  <fencedframe style="width:200px; height: 200px;" aria-label="Scrollable iframe">
  </fencedframe>
  <script>
    window.onload = () => {
      const url = new URL("frame/visible_text.html", location.href);
      document.querySelector("fencedframe").config = new FencedFrameConfig(url);
    }
  </script>
</body>
</html>