The track you select in the mixer, or in the project page?
I have a CC121, and that one follows whatever is open and selected in the project page.
If I hide tracks (or collapse a folder) in the project page, I can’t use the controller itself to move across the mixer and select those tracks.
Then I have to use the mouse to select the track, and the controller will follow.
The controllers should follow visible and selected tracks/channels in the mixer, no matter what were hidden in the project page IMO.
Not the other way around.
PS. I work sometimes in Studio One, and a faderport is on my shortlist.
I know this is said to be working in many DAW’s. Thanks for reporting.