One of my favorite Unity features is the ability to pin windows to one side of the screen or the other. My tendency to do this a lot has made me notice a bug where when I'm moving a Firefox window I get the clenched fist and even after letting go of the window the pointer never returns to normal. After this I'm unable to use the mouse normally until I do a
killall firefox from the terminal.
How do I pinpoint the source of this error since I cannot reliably reproduce it, and I'm not sure of all of the systems that might be involved?
Firefox 13.01 seen on both Ubuntu 10.04 and 12.04