Add language filters to federated and local timelines

[germanfr]

Is your feature request related to a problem? Please describe.
I would like to have the option to filter out the toots that are not in a language that I don't understand from the federated and local feeds.

I often find myself there to see outside of my timeline or to find people to follow, but there's a lot of people that speak other languages, and this is not what I am interested in.

Describe the solution you'd like
I think a good place to put this option would be in the "edit timelines" menu. That way you can individually choose the languages for each timeline.
Maybe I want to have one in my language and another one to also have English. This could also apply for followed hashtags.

Describe alternatives you've considered
What I do now is I have saved local feeds of other instances that are language specific, but this doesn't work if I want to do the same in big general instances like mastodon.social for example, or the federated timeline.

Additional context
I don't know how it works but I think toots must have like a language tag. This could be used to filter them.

[germanfr]

I know this can be done because I can search language:es and it works.