@sneaker_ger:
Damn, never got this feature. Thank you very much for pointing to it, will try it!
@SeeMoreDigital:
Yeah, its also some kind of extraction ... you extract specific tracks out. I think extraction does not mean you get always multiple files for each track, so it was not so far away from being "legit" to ask for it.
You can extract tracks directly into a new mkv, or is there another word to describe this type of extraction better? Of course it is always also some kind of remuxing. But without saving it to seperate files I would call it "extracting into single file".
Demuxing is a clear process (with multiple output) in my eyes, but extracting is a bit unprecise and gives some room for interpretation ...