<html xmlns="http://www.w3.org/1999/xhtml" class="reftest-wait">
<head>
<script>

var HTML_NS = "http://www.w3.org/1999/xhtml";

function boom()
{
  var a = document.getElementById("a");
  var plus = document.getElementById("plus");
  var frameset = document.createElementNS(HTML_NS, "frameset");
  
  document.body.style.width = "300px";

  a.parentNode.removeChild(a);
  
  plus.appendChild(frameset);
  
  document.documentElement.removeAttribute("class");
}

</script>
</head>

<body onload="setTimeout(boom, 30);">

<div><math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
  <msup>
    <mi id="a">a</mi>
    <mo id="plus">+</mo>
    <mi>b</mi>
    <mi>c</mi>
  </msup>
</math></div>

</body>

</html>