chromium/third_party/blink/web_tests/paint/theme/anonymous-element-menulist-painting.html

<script>
  if (window.testRunner) {
    testRunner.dumpAsText();
  }
</script>
 <style>
  ::-webkit-scrollbar {
    -webkit-appearance: menulist;
  }
  .scroll-container {
    overflow: scroll;
    width: 100px;
    height: 100px;
  }
  .child {
    width: 200px;
    height: 200px;
  }
</style>
<div class="scroll-container"><div class="child"></div></div>