chromium/third_party/blink/web_tests/external/wpt/css/css-contain/content-visibility/content-visibility-078.html

<!doctype HTML>
<html class="reftest-wait">
<meta charset="utf8">
<title>CSS Content Visibility: positioned movement update moves hidden container</title>
<link rel="author" title="Vladimir Levin" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-contain/#content-visibility">
<link rel="match" href="content-visibility-078-ref.html">
<meta name="assert" content="when locked, position updates still apply">

<script src="/common/reftest-wait.js"></script>

<style>
.hidden { content-visibility: hidden; }
#target {
  top: 50px;
  left: 0;
  position: absolute;
  width: 100px;
  height: 100px;
  background: blue;
}
#t2 {
  top: 150px;
  left: 100px;
  position: absolute;
  width: 100px;
  height: 100px;
  background: orange;
}
</style>

<p>Test passes if the blue and orange boxes are vertically aligned with each other.
<div id=target class=hidden>FAIL</div>
<div id=t2 class=hidden>FAIL</div>

<script>
function runTest() {
  target.style = "left: 100px;";
  takeScreenshot();
}

window.onload = () => requestAnimationFrame(() => requestAnimationFrame(runTest));
</script>