I started a new project and loaded in 8 stereo tracks. I did View > Fit Vertically on my 1920x1080 22" monitor. I then discovered by chance that, although the Mute and Solo buttons were no longer visible, their function was still available if I moused carefully. The aiming point had to be just above and just outside the corners of the button (at centre bottom of each Track Details panel) that allows the track to be fully minimised. Once I had identified this “target zone” I found it very useful being able to Mute and Solo tracks just as if the two buttons were actually visible. Neat! If it’s a bug, please don’t fix it!
“Is this a bug or a feature?”
In my opinion, neither. It’s a “quirk”
The buttons disappear (are not drawn) as soon as they are partially obscured, but the “hot zone” does not disappear until it is fully obscured.
Personally I think it would be useful if the track controls were moved higher up (above the track info) so that they are visible for less high tracks.
I think there is a proposal and/or feature request for this.
If it’s a bug, please don’t fix it!