<style>
rt, embed {
  height: 4px;
  line-height: 100vh;
}
</style>

<script>
if (window.testRunner)
  testRunner.dumpAsText();

window.addEventListener("load", function () {
  document.body.offsetHeight;
  document.all[6].appendChild(rt);
  document.body.offsetHeight;
  appendToThis.appendChild(rt);
});
</script><rt id=rt>PASS if no crash or assert</rt><ruby id=foo><span id=appendToThis></span><embed type="unspecified"></embed>
</ruby>