background-attachment-local-composited.html

<!DOCTYPE html>
<style>
::-webkit-scrollbar {
  display: none;
}
#container {
  overflow: scroll;
  will-change: transform;
  width: 400px;
  height: 400px;

  background-attachment: local;
  background-color: blue;
}

#child {
  height: 500px;
}
</style>
<div id="container">
  <div id="child"></div>
</div>
<script src="../resources/text-based-repaint.js"></script>
<script>
function repaintTest() {
  child.style.height = '2000px';
  container.scrollTop = 2000;
}
onload = runRepaintAndPixelTest;
</script>

chromium/third_party/blink/web_tests/paint/invalidation/compositing/background-attachment-local-composited.html