Whenever the new "Firefox" drop-down menu is enabled (i.e. "Menu Bar" is disabled under View -> Toolbars -> Menu Bar), the title bar (the area of the window adjacent to the "Firefox" button and the minimize/maximize/close buttons) blinks every so often, seemingly randomly, usually a couple of times per minute. Note that when Menu Bar is enabled, no blinking occurs. This doesn't appear to affect performance, but it is pretty annoying. I'm running Windows 7 and I have the transparency options enabled. == This happened == Every time Firefox opened == I installed Firefox 4 beta