It is nice that the environment variables `LANG` & `LANGUAGE` can be used to override the system locale. But I think it would be even more user friendly to have a configuration option under preferences that would override both system & environment specified language.
It seems there are quite a few users who think there is no locale support or just aren't sure how to change languages. While "I don't have time to read the docs" generally isn't a good excuse, being able to configure the language from within the UI will lead to less confusion, especially for non-Posix system users.
If I get time, I may see if I can add the option myself & create a pull/merge request.
Some related threads: - #1757 - #2831 - #2619 - #2545 <- I think this one is an especially good reason for a configuration option - #1910