Okay, I did your test. Everything worked as you would expect it to. I opened and empty session and added 8 tracks. The Enlarge Selected Track preference was already active so, the 1st track was enlarged. I resized it down a little. Then I switched to track 6. Track 1 became the same size as the others and track 6 went to the enlarged size that I had set seconds earlier. When I deactivated the preference, All tracks went to the same size. I enlarged track 1, then switched to track 6. Track 1 remained enlarged. But that’s the NORMAL, exactly what you’d expect behavior. So, what does this mean?
The screen shot I showed was from a project with 100+ tracks of various types. It started out with all of them working just like the tracks did in this test. Then it just kind of happened after a few days of working on the project. first the MIDI tracks did it, then the audio tracks did it. I did a global shrink and reset of ALL the tracks and it made no difference. It doesn’t effect the work, but it is annoying as hell!
I thought it might be in the template. So I created new ones. But it still happens randomly from project to project. Sometimes I’ll go 3 or 4 projects without it happening. So, I don’t notice anything, since it’s working like it should. Then I’ll get one that requires a lot of MIDI editing, which may have 3 or 4 “EDIT IN PLACE” tracks open at the same time and then it’ll happen. That’s as close I can get to a known possible cause. I’m wondering if it’s a bug or the system just isn’t wired to handle multiple MIDI tracks open in that state.