Bug#791506: [www.debian.org] Content negotiation doesn't work properly with pt_BR at the Release Notes web page

Hello

Content negotiation works well: if you have pt-BR and pt locales enabled in 
browser, and go to https://www.debian.org/releases/bullseye/releasenotes you are 
presented a "pt" translation of the page (because there is no pt-br translation 
of that page) and thus the links to "Português" are in bold instead of the links 
to "Português (Brasileiro)".
OTOH if you click the links that are on top of the page (e.g. "Release Notes 
para PC 64 bits (amd64)") or go directly to 
https://www.debian.org/releases/bullseye/amd64/release-notes/, you will get the 
pt-br translation of the release notes (because for release notes, there are pt 
and pt-br versions).

Notes:
1.- Our website does not admit, currently, pt + pt-br variants (the release 
notes docs allow pt and pt-br, but not our webwml pages).
2.- If a person only has pt-br locale (and not "pt"), for the webwml pages they 
will get a fallback language, because in the config of Apache of our website we 
say that for pt-br they should serve a pt-br page (not a pt one):

https://salsa.debian.org/dsa-team/mirror/dsa-puppet/-/blob/production/modules/roles/templates/apache-www.debian.org.erb

But if we'd change the Apache config to serve .pt files for pt-br locale, I 
think that the pt-br versions of release notes and maybe other documents 
wouldn't be served.

So (correct me if I'm wrong) I think the best is leave things as they are, 
suggest users to include both pt-br and pt locales in their browser, and close 
this bug.

CC'ing the Portuguese language team, for the case I'm missing something or they 
have a better idea.

Kind regards,