chromium/third_party/blink/web_tests/external/wpt/css/css-contain/reference/contain-layout-021-ref.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Containment Test: Layout containment fixed positioned descendants</title>
<style>
#green {
  background: green;
  width: 100px;
  height: 100px;
}
body {
  height: 3000px;
  margin: 0px;
}
#spacer {
  height: 200px;
}
</style>
<script>
function runTest() {
  document.documentElement.scrollTop += 200;
}
</script>
<body onload="runTest()">
<div id="spacer"></div>
<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
<div id="green"></div>
</body>