Man pages matching name flcheckers in section 6:

flcheckers.6.en	debian 10 / fltk1.1-games
flcheckers.6.en	debian 10 / fltk1.3-games
flcheckers.6.en	debian 11 / fltk1.1-games
flcheckers.6.en	debian 11 / fltk1.3-games
flcheckers.6.en	debian 12 / fltk1.1-games
flcheckers.6.en	debian 12 / fltk1.3-games