<html xmlns="http://www.w3.org/1999/xhtml" class="reftest-wait">
<head>
<script>

function boom()
{
  var tr2 = document.getElementById('tr2');
  var newTD = document.createElement('td');
  newTD.setAttribute('colspan', 2);
  newTD.appendChild(document.createTextNode('x'));
  tr2.insertBefore(newTD, document.getElementById('b'));
  
  document.getElementById('a').setAttribute('colspan', 1);
  document.getElementById('b').setAttribute('colspan', 3);

  document.documentElement.removeAttribute("class");
}

</script>
</head>

<body onload="setTimeout(boom, 250);">

<table style="border-collapse: collapse;" border="1">
  <tbody>
    <tr>
      <td id="a" colspan="3">A</td>
    </tr>
    <tr id="tr2">
      <td id="b">B</td>
    </tr>
    <tr>
      <td>C</td>
    </tr>
  </tbody>
</table>

</body>
</html>