Man pages matching name catmandu::plugin::readonly in section 3pm:

Catmandu::Plugin::Readonly.3pm.en	debian 10 / libcatmandu-perl
Catmandu::Plugin::Readonly.3pm.en	debian 11 / libcatmandu-perl
Catmandu::Plugin::Readonly.3pm.en	debian 12 / libcatmandu-perl