I thought when you Alt+F8 a section the track state is then set to frozen but you can still Alt+F8 other sections on that track still but it won't destroy everything if you hit Gen/Play ?

If you had freeze individual sections you would need to keep track of them all, maybe in the Audio Edit view highlight that section of track on that instrument (bars or beats) then right click Freeze Section then it will have a blue overlay color maybe ? and right click Un-Freeze Section or Un-Freeze All Sections ?
It would have to work with midi also for when they add that multiriff for midi function, so maybe that could use the Audio Edit window of the midi track ?

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