chromium/third_party/blink/web_tests/external/wpt/css/css-view-transitions/backdrop-filter-captured.html

<!DOCTYPE html>
<html class="reftest-wait">
<title>View transitions: capture with backdrop filter on the element</title>
<link rel="help" href="https://drafts.csswg.org/css-view-transitions-1/">
<link rel="author" href="mailto:[email protected]">
<link rel="match" href="backdrop-filter-captured-ref.html">
<script src="/common/reftest-wait.js"></script>
<style>
.box {
  background: green;
  width: 100px;
  height: 100px;
}
#target {
  view-transition-name: target;
  width: 50px;
  height: 50px;
  position: absolute;
  top: 20px;
  left: 20px;
  backdrop-filter: grayscale(1);
}

html::view-transition-group(*) { animation-duration: 300s; }
html::view-transition-new(*) { animation: unset; opacity: 1; }
html::view-transition-old(*) { animation: unset; opacity: 0; }
</style>
<div class=box></div>
<div id=target></div>

<script>
failIfNot(document.startViewTransition, "Missing document.startViewTransition");

async function runTest() {
  document.startViewTransition().ready.then(takeScreenshot);
}
onload = () => requestAnimationFrame(() => requestAnimationFrame(runTest));
</script>
</html>