The "Federated #timeline" can only become useful (a success function) if it's possible to:

1) Effectively filter languages, and
2) Filter by hashtag(s), and
3) Make saved variants of the combination of 1) and 2) that can be easily reused

A tabbed or prev/next inferface and/or "carousel" function might let us conveniently switch the column view between such variants.

Filter/"variant" examples:

"English" + "#ITsecurity"
"Scandinavian" + "local news"
"German" + "EU" + "legislation"

#Mastodon

I am trying to get to like/use #Mastodon by actually communicating through it.

However, it would seem ironic if it is "moot" to communicate about Mastodon features etc. here, in case that is better done at https://discourse.joinmastodon.org ? (@Gargron ?)

Mastodon might be THE tool that would make me interact and contribute MUCH more towards any target community if it had #integration and could serve as front-end client for such communication.

#MastodonStrategy
#collaboration
#onetomany

@ZeniorXV Combination of all the three your points can currently be done in #AndStatus at least with #Twitter, where language selection can be a part of a query string, see https://github.com/andstatus/andstatus/issues/442
Not very convenient to configure, but it works and syncs automatically!