checkbutton(3tk) on Linux
The text 4ff0f2df679e, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch) shipped it. The page shows this text now.
Create and manipulate 'checkbutton' boolean selection widgets