chromium/content/test/data/accessibility/css/visibility-to-visible.html

<!--
@WAIT-FOR:done
-->
<div>
  Cats
  <span id="visible" style="visibility:hidden;">
      <input type="checkbox" aria-label="checkbox">
  </span>
  <div><code>pending</code></div>
</div>
<div role="group" id="visible2" style='visibility: hidden'><mark>text</mark></div>

<script>
  setTimeout(()=> {
    document.getElementById('visible').style.visibility = 'visible';
    document.getElementById('visible2').style.visibility = 'visible';
    document.querySelector('code').innerText = 'done';
  }, 200);
</script>