<!DOCTYPE html>
<html class="reftest-wait">
<head>
<meta charset="UTF-8">
<script>

function boom()
{
  var frameDoc = document.getElementById("f").contentDocument;
  var frameRoot = frameDoc.documentElement;
  frameDoc.write("");
  frameRoot.setAttribute("onload", "");
  frameRoot.onload;
  document.documentElement.removeAttribute("class");
}

</script>
</head>

<body onload="boom();">
<iframe id="f" srcdoc="1"></iframe>
</body>
</html>