I used Chmox to view a .chm file, then closed by
clicking in the close windows widget. It closed but
left a white rectangle on the screen (I'm assuming that
it didn't repaint) against the screen background of
blue. This persisted until I exited by selecting quit
chmox from menu bar.
I'm using a Mac-mini; 1.42GHz G4 processor; 1GB ram;
Mac OS X 10.3.7. All OS updates loaded current to 1/29/05.