I don't know if this only happens in FF3 and Opera 9.5 or even in earlier versions, but when you are clicking on web site with embedded flash the whole site blinks, like it is redrawn again. If i describe you in a slow motion, it first shows the white background and then the page. For instance, open youtube and try clicking on videos thumbnails on a side. Do you see the blinking? This must be some kind of browser or maybe even flash bug, because IE and Safari are rendering pages just fine. Its also interesting that this only happens on windows, meanwhile same browser in linux rendering just fine. Tested with firefox 3.0.1 and opera 9.5 and flash player 9.0 r124.