It would be useful to have an event handler when a user triggers an action from the action menu. possible parameters could be:

[Number action_id, String action_name, Object unit]

This would be very useful for canceling actions, especially native Arma 3 actions.

Example usage: in the instance of disassembling a static mortar an event handler could disable this. To my knowledge with the current framework there is no such way of doing this.