When Visual Task Tips is installed (http://download.cnet.com/Visual-Task-Tips/3000-2094_4-10766659.html) under XP SP3, when jEdit is open, but another task is in the foreground, holding the mouse over the jEdit taskbar icon intermittently causes jEdit to redraw itself, overdrawing the foreground task. Also, even when not holding the cursor over a taskbar icon, jEdit will still overdraw the foreground tasks in 5-30 minutes (I haven't timed it exactly) more reliably. I believe it is due to the call(s) that Visual Task Tips makes, to capture an image of a task's window; which jEdit seems to require overdrawing the foreground windows to do. It would be best to be able to send Visual Task Tips an image of jEdit's window without redrawing the foreground. Next best would be to simply pass it a black square the size of the window. Some applications do only generate black taskbar window previews; but no other applications that I use, in any event, overdraw the foreground windows in this way.