- :normal
 - Crossing because of pointer motion.
       - :grab
 - Crossing because a grab is activated.
       - :ungrab
 - Crossing because a grab is deactivated.
       - :gtk-grab
 - Crossing because a GTK grab is activated.
       - :gtk-ungrab
 - Crossing because a GTK grab is deactivated.
       - :state-changed
 - Crossing because a GTK widget changed state, for        example sensitivity.
       - :touch-begin
 - Crossing because a touch sequence has begun, this        event is synthetic as the pointer might have not left the window.
       - :touch-end
 - Crossing because a touch sequence has ended, this event        is synthetic as the pointer might have not left the window.
       - :device-switch
 - Crossing because of a device switch, that is, a
        mouse taking control of the pointer after a touch device, this event is        synthetic as the pointer did not leave the window.