css/css-position/position-change.html

<!doctype HTML>
<html class="reftest-wait">
  <title>CSS Test: Test for re-paint after position change</title>
  <link rel="author" title="Philip Rogers" href="mailto:pdr@chromium.org" />
  <link rel="help" href="https://www.w3.org/TR/CSS2/zindex.html">
  <link rel="match" href="position-change-ref.html">
  <script src="/common/reftest-wait.js"></script>

  <div style="position: relative; background: red; width: 100px; height: 100px; overflow: hidden;">
    <div id="target" style="overflow-y: scroll; width: 400px; height: 400px; position: relative;">
      <div style="height: 100px; width: 100px; background: green;"></div>
      <!-- forces scrolling -->
      <div style="height: 700px;"></div>
    </div>
  </div>

  <script>
    onload = function() {
      requestAnimationFrame(() => requestAnimationFrame(() => {
        target.style.position = "";
        takeScreenshot();
      }));
    }
  </script>
</html