This appears to be a conflict between gtk-window-decorator and compiz itself. if you kill the decorator, then Alt-Button3 acts as configured in compiz. gtk-window-decorator --minimal also seems to disable the key binding, but also disables the other decorations as well.
This appears to be a conflict between gtk-window- decorator and compiz itself. if you kill the decorator, then Alt-Button3 acts as configured in compiz. gtk-window- decorator --minimal also seems to disable the key binding, but also disables the other decorations as well.