LayoutTests/editing/execCommand/150252.xhtml

<div id="150252" xmlns="http://www.w3.org/1999/xhtml">

<script type="text/javascript">

function boom()
{
  if (window.testRunner)
    testRunner.dumpAsText();

  var r = document.documentElement;
  r.style.position = "absolute";
  r.contentEditable = "true";
  r.focus();
  r.contentEditable = "false";
  r.focus();
  r.contentEditable = "true";
  document.execCommand("subscript", false, null);
  r.contentEditable = "false";
  document.getElementById("150252").innerHTML = "This test passes if it doesn't crash. https://bugs.webkit.org/show_bug.cgi?id=150252";
}

window.addEventListener("load", boom, false);

</script>

</div>