Every time I update Firefox the language changes to English and I have to manualy add and change it back to Polish; why added languages do not stay (only Eng)?
In the Options > Language it is always only English after every update of Firefox. I then add Polish, every time, but it doesn't stay there. Another update and all of it repeats. Any suggestions?
Did you install the English Firefox and then a language pack? Or did you install in whatever language you wanted?
Is this about language packs for the user interface?
- Options/Preferences -> Languages
Choose the languages used to display menus, messages, and notifications from Firefox.
These language packs should also be displayed under "Options/Preferences -> Languages". Do you see them there? You may also have a pref named "intl.locale.requested" with the currently selected language.
The preferred languages for web pages is stored in a pref named "intl.accept_languages".
It is possible that there is a problem with the preferences if you do not keep settings.
Note that you may have to update language pack manually on about:addons -> Languages.