al_remove_display_menu - Allegro 5 API

       Detaches  the  menu associated with the display and returns it.  The menu can then be used on a different
       display.

       If you simply want to destroy the active menu, you can  call  al_set_display_menu(3alleg5)  with  a  NULL
       menu.

       al_remove_display_menu - Allegro 5 API

al_set_display_menu(3alleg5)

Allegro reference manual                                                         al_remove_display_menu(3alleg5)

       5.1.0

              #include <allegro5/allegro_native_dialog.h>

              ALLEGRO_MENU *al_remove_display_menu(ALLEGRO_DISPLAY *display)