When /Exit is requested (eg. during an update) if XMBC settings window is open and has a sub-dialog like Simkey, chording, buttonheld etc. then the exit does not succeede. The settings window closes but the child window is left hanging around.
The child windows should also be closed, allowing XMBC to fully exit (it may not be graceful, and settings may be lost, but at least it will exit!)
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