Man pages matching name syntax::highlight::perl::improved in section 3pm:

Syntax::Highlight::Perl::Improved.3pm.en	debian 10 / libsyntax-highlight-perl-improved-perl
Syntax::Highlight::Perl::Improved.3pm.en	debian 11 / libsyntax-highlight-perl-improved-perl
Syntax::Highlight::Perl::Improved.3pm.en	debian 12 / libsyntax-highlight-perl-improved-perl