Noticed a difference in text based repaints rects between WK1 and WK2 for the following html test: <html> <head> <script src="../../repaint/resources/text-based-repaint.js"></script> <style> body { margin: 0px; } #parent { position: fixed; top: 50px; left: 50px; width: 100px; height: 100px; } .transformed { -webkit-transform: scale3d(1, 1, 1); } </style> </head> <body onload="runRepaintTest()"> <div id="parent"></div> <script> function repaintTest() { document.getElementById("parent").className = "transformed"; } </script> </body> </html>