Man pages matching name plack::middleware::test::stashwarnings in section 3pm:

Plack::Middleware::Test::StashWarnings.3pm.en	debian 10 / libplack-middleware-test-stashwarnings-perl
Plack::Middleware::Test::StashWarnings.3pm.en	debian 11 / libplack-middleware-test-stashwarnings-perl
Plack::Middleware::Test::StashWarnings.3pm.en	debian 12 / libplack-middleware-test-stashwarnings-perl