chromium/third_party/blink/web_tests/scrollbars/custom-scrollbar-change-style-crash.html

<!DOCTYPE html>
<style>
::-webkit-scrollbar {
  width: 20px;
}
::-webkit-scrollbar-thumb {
  z-index: 300;
}
::-webkit-scrollbar-thumb:window-inactive {
  position: fixed;
}
</style>
<div style="height: 20px; width: 1500px"></div>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script>
test(function() {
  document.body.offsetTop;
  if (window.testRunner)
    testRunner.setWindowFocus(false);
}, 'crash test when a custom scrollbar changes style related to stacking context');
</script>