Add special keyword to allow all languages

[janbo208]

I would like an option to allow all languages in the filters section.

I don't think it's very practical to add a long list language codes to the allowed list if you want to accept everything. Adding a keyword i.e. ["all"] would be very useful.

[rbraunschweig]

You can also use the ignore keyword in allowed_languages.

[janbo208]

That's good to know, thank you.