<!DOCTYPE html>
<html>
<head>
<script>

var t;

function boom()
{
  var b = document.createElementNS("http://www.w3.org/1999/xhtml", "body");
  t = document.createElementNS("http://www.w3.org/1999/xhtml", "textarea");
  b.appendChild(t);
  document.removeChild(document.documentElement)
  document.appendChild(b)
  document.removeChild(document.documentElement)
  var ns = document.createElementNS("http://www.w3.org/1999/xhtml", "script");
  var nt = document.createTextNode("t.appendChild(document.createTextNode(' '));");
  ns.appendChild(nt);
  b.appendChild(ns);
  document.appendChild(b);
}

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