chromium/content/test/data/accessibility/html/whitespace-dynamic.html

<!--
@WAIT-FOR:Done
-->

<!doctype HTML>
<div tabindex="0" id="status" aria-label="Working"></div>
<p id=p style="visibility:hidden">
Should end up with a trailing whitespace 
</p>
<script>
setTimeout(() => {
  let a = document.createElement("a");
  a.innerText = "link";
  p.appendChild(a);
  setTimeout(() => {
    document.getElementById('status').setAttribute('aria-label', 'Done');
  }, 0);
}, 1000);
</script>