[Pkg-mailman-hackers] Template files installed by mailman3 package are empty for some languages

[Elias Rudberg]

Hello,

I'm using the mailman3 Debian package and recently it happened that 
Swedish language was selected by an admin, which had the effect that 
emails sent by mailman to users (for example the "Your confirmation is 
needed to join..." emails) had an empty email body.

This seems to be because the template files installed in 
/usr/lib/python3/dist-packages/mailman/templates/ are empty for some 
languages, including Swedish.

For example this file is empty:

/usr/lib/python3/dist-packages/mailman/templates/sv/list:user:action:subscribe.txt

The corresponding English language file is not empty:

/usr/lib/python3/dist-packages/mailman/templates/en/list:user:action:subscribe.txt

The upstream git repo seems to have the file, it looks fine there:

https://gitlab.com/mailman/mailman/-/blob/master/src/mailman/templates/sv/list:user:action:subscribe.txt

But why is it not in the debian package?

It seems like the template files are empty for the following languages 
(not all, just these 14 of 34 languages):

ar
bn
el
eo
fa
fi
hu
nb_NO
oc
pl
si
sq
sv
zh_Hant

As far as I can tell, it's like this in Debian trixie and also in forky.

Why are those template files empty?

Should it be reported as a bug?

/ Elias