clip-path-url-reference-change-from-empty.html

<!DOCTYPE html>
<html class="reftest-wait">
<title>Switch from an empty to a non-empty clip-path url()</title>
<link rel="help" href="http://www.w3.org/TR/css-masking-1/#clipping-paths">
<link rel="help" href="http://www.w3.org/TR/css-masking-1/#the-clip-path">
<link rel="match" href="reference/green-100x100.html">
<script src="/common/reftest-wait.js"></script>
<svg>
  <clipPath id="empty"/>
  <clipPath id="rect">
    <rect width="100" height="100"/>
  </clipPath>
  <rect width="100" height="100" fill="red"/>
  <rect width="100" height="100" fill="green" id="target" clip-path="url(#empty)"/>
</svg>
<script>
  requestAnimationFrame(() => {
    requestAnimationFrame(() => {
      document.getElementById('target').setAttribute('clip-path', 'url(#rect)');
      takeScreenshot();
    });
  });
</script>

chromium/third_party/blink/web_tests/external/wpt/css/css-masking/clip-path/clip-path-url-reference-change-from-empty.html