chromium/third_party/blink/web_tests/external/wpt/css/css-position/z-index-blend-will-change-overlapping-layers.html

<!DOCTYPE html>
<html class="reftest-wait">
<title>z-index, will-change, mix-blend-mode on overlapping layers</title>
<link rel="match" href="z-index-blend-will-change-overlapping-layers-ref.html">
<link rel="help" href="https://www.w3.org/TR/CSS2/visuren.html#propdef-z-index">
<link rel="help" href="https://drafts.csswg.org/css-will-change/#will-change">
<link rel="help" href="https://www.w3.org/TR/compositing-1/#mix-blend-mode">
<meta name="assert" content="Tests z-index, will-change and mix-blend-mode on overlapping layers.
Passes if there is a green bar when the page is scrolled to the bottom.">
<script src="/common/reftest-wait.js"></script>
<div style="z-index: 1; position: relative; height: 100vh">
  <div style="mix-blend-mode: multiply"></div>
  <div style="will-change: transform; position: absolute; bottom: -100px; width: 100px; height: 100px; background: red">
  </div>
</div>
<div style="z-index: 1; position: relative; background: green; height: 100px"></div>
<script>
requestAnimationFrame(()=>{
  requestAnimationFrame(()=>{
    window.scrollBy(0, 100);
    takeScreenshot();
  });
});
</script>
</html>