LayoutTests/fast/editing/mutation-with-display-contents-container-crash.html

<style>
  div {
    display: contents;
  }
  b, span {
    border-style: ridge;
    float: right;
  }
  b {
    font-weight: inherit;
  }
</style>
<div>This test passes if it does not crash.</div>
<script>
  if (window.testRunner)
      testRunner.dumpAsText();
  onload = () => {
    document.documentElement.appendChild(document.createElement('b'));
    document.documentElement.appendChild(document.createElement('span'));
    document.execCommand('SelectAll');
    document.execCommand('Copy');
    document.designMode = 'on';
    document.execCommand('Paste');
  };
</script>