<style>
  head, script {
    display: table;
  }
</style>
<script>
  if (window.testRunner)
      testRunner.dumpAsText();
  onload = () => {
    console.log("This test passes if it does not crash.");
    document.execCommand('SelectAll');
    document.execCommand('Copy');
    document.execCommand('SelectAll');
    document.designMode = 'on';
    document.execCommand('PasteAndMatchStyle');
  };
</script>