Man pages matching name getopt::argparse::actionappend in section 3pm:

Getopt::ArgParse::ActionAppend.3pm.en	debian 10 / libgetopt-argparse-perl
Getopt::ArgParse::ActionAppend.3pm.en	debian 11 / libgetopt-argparse-perl
Getopt::ArgParse::ActionAppend.3pm.en	debian 12 / libgetopt-argparse-perl