<html class="reftest-wait"> <head> <script> function boom() { document.body.offsetHeight; var fivediv = document.getElementById("five"); var parent = fivediv.parentNode; for (var i = 3; i <= 4; i++) { var newdiv = document.createElement("div"); newdiv.appendChild(document.createTextNode(i)); parent.insertBefore(newdiv, fivediv); } var fivedeediv = document.getElementById("fivedee"); parent = fivedeediv.parentNode; var newdiv = document.createElement("div"); newdiv.appendChild(document.createTextNode("5b")); parent.insertBefore(newdiv, fivedeediv); newdiv = document.createElement("div"); newdiv.appendChild(document.createTextNode("5c")); parent.insertBefore(newdiv, fivedeediv); document.body.offsetHeight; document.documentElement.className = ""; } </script> </head> <body onload="boom();"> <div>1</div> <div>2</div> <div id="five"> <div>5a</div> <div id="fivedee">5d</div> </div> <div>6</div> <div>7</div> <div>8</div> <div>9</div> </body> </html>