New comment by Chocimier on void-packages repository

https://github.com/void-linux/void-packages/issues/27255#issuecomment-1036412009

Comment:
Again: I am pretty sure it is manually installed translation overriding system one.

In new clean profile, is translation present? (`firefox -P`, then start with new profile. The profile selector is English only.)
If it is, try to remove translation from your main profile and restart browser.