Man pages matching name gendiff in section 1:

gendiff.1.en	debian 10 / rpm
gendiff.1.pl	debian 10 / rpm-i18n
gendiff.1.de	debian 11 / manpages-de
gendiff.1.en	debian 11 / rpm
gendiff.1.pl	debian 11 / rpm-i18n
gendiff.1.en	debian 12 / rpm
gendiff.1.pl	debian 12 / rpm-i18n