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

function boom()
{
  var mo = document.createElementNS("http://www.w3.org/1998/Math/MathML", "mo");
  var text = document.createTextNode(" ");
  mo.appendChild(text);
  document.body.appendChild(mo);

  window.getSelection().removeAllRanges();
  var r = document.createRange();
  r.setStart(mo.firstChild, 0);
  r.setEnd(mo.firstChild, 1);
  window.getSelection().addRange(r);

  window.getSelection().toString();
}

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