Once this is implemented in the REST API, change Postorius forms.py so it calls the API to ask that question when a list administrator is setting up a new list or changing preferences for a list, instead of hardcoding English as the only choice for the list's preferred language.
Also affects Postorius.
Once this is implemented in the REST API, change Postorius forms.py so it calls the API to ask that question when a list administrator is setting up a new list or changing preferences for a list, instead of hardcoding English as the only choice for the list's preferred language.