Title: Buttons Not Highlighted If Mouse-Pointer Over Them Using GTK+
In the GTK+ Look-And-Feel, a toggle-button (such as the chord-pad buttons) will not show its highlighting (selection) if the mouse-pointer is over it.
Cause Of Problem:
This appears to be the way Java Swing works in the GTK+ look-and-feel.
Keep the mouse-pointer away from toggle-buttons if you're using the GTK+ look-and-feel, or use a different look-and-feel.
Fix Available (in version):