Man pages matching name unicode::casefold in section 3pm:

Unicode::CaseFold.3pm.en	debian 10 / libunicode-casefold-perl
Unicode::CaseFold.3pm.en	debian 11 / libunicode-casefold-perl
Unicode::CaseFold.3pm.en	debian 12 / libunicode-casefold-perl