LayoutTests/fast/animation/animation-cascade-crash.html

<style>
  body {
    transition-duration: 1ms;
    width: revert;
  }
</style>
<script>
  if (window.testRunner)
        testRunner.dumpAsText();
  onload = () => {
    document.styleSheets[0].insertRule(`body { width: 0em; }`);
    document.styleSheets[0].insertRule(`html { font-size: 0; }`);
  };
</script>
This test passes if it doesn't crash.