Man pages matching name plack::middleware::debug::environment in section 3pm:

Plack::Middleware::Debug::Environment.3pm.en	debian 10 / libplack-middleware-debug-perl
Plack::Middleware::Debug::Environment.3pm.en	debian 11 / libplack-middleware-debug-perl
Plack::Middleware::Debug::Environment.3pm.en	debian 12 / libplack-middleware-debug-perl