<html class="reftest-wait"> <head> <style> colgroup#s { width: 200px; } </style> <script> function boom() { document.body.offsetHeight; var last = document.getElementById("last"); var parent = last.parentNode; var colgroup = document.createElement("colgroup"); colgroup.setAttribute("id", "s"); parent.insertBefore(colgroup, last); var newtbody = document.createElement("tbody"); var newrow = document.createElement("tr"); var newcell = document.createElement("td"); newcell.appendChild(document.createTextNode("cell 1,1")); newrow.appendChild(newcell); newcell = document.createElement("td"); newcell.appendChild(document.createTextNode("cell 1,2")); newrow.appendChild(newcell); newtbody.appendChild(newrow); parent.insertBefore(newtbody, last); document.body.offsetHeight; document.documentElement.className = ""; } </script> </head> <body onload="boom();"> <table border="1"> <colgroup></colgroup> <tbody id="last"><tr><td>cell 2,1</td><td>cell 2,2</td></tr></tbody> </table> </body> </html>