When you add a new button to an existing menu in
user_initialize(), you are modifying the definition of the menu in its memory before that menu has been used by , and therefore before has loaded it from its menu file. You must call the function
ProMenuFileRegister() to tell to load its own menu file before you can add your own buttons.
To add a button to a menu, first write a menu file, and then add the following calls to user_initialize():