Man pages matching name palette_color in section 3alleg4:

palette_color.3alleg4.en	debian 10 / allegro4-doc
palette_color.3alleg4.en	debian 11 / allegro4-doc
palette_color.3alleg4.en	debian 12 / allegro4-doc
palette_color.3alleg4.en	debian 13 / allegro4-doc