<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">

function boom()
{
  document.removeChild(document.documentElement)
  document.appendChild(document.createElementNS("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul", "hbox"));
}

</script>
</head>
<body onload="boom();"></body>
</html>