Man pages matching name mason::plugin::routersimple in section 3pm:

Mason::Plugin::RouterSimple.3pm.en	debian 10 / libmason-plugin-routersimple-perl
Mason::Plugin::RouterSimple.3pm.en	debian 11 / libmason-plugin-routersimple-perl
Mason::Plugin::RouterSimple.3pm.en	debian 12 / libmason-plugin-routersimple-perl