<html class="reftest-wait">
<head>

<script>
function boom()
{
  document.body.offsetHeight;

  var fourdiv = document.getElementById("four");
  var parent = fourdiv.parentNode;

  var newdiv = document.createElement("div");
  newdiv.appendChild(document.createTextNode("3"));
  parent.insertBefore(newdiv, fourdiv);

  document.body.offsetHeight;
  document.documentElement.className = "";
}
</script>

</head>
<body onload="boom();">
<div>1</div>
<div>2</div>
<div id="four">4</div>
<div>5</div>
</body>
</html>