Man pages matching name al_win_add_window_callback in section 3alleg5:

al_win_add_window_callback.3alleg5.en	debian 10 / allegro5-doc
al_win_add_window_callback.3alleg5.en	debian 11 / allegro5-doc
al_win_add_window_callback.3alleg5.en	debian 12 / allegro5-doc