GOP updates not working properly since 2.4.4

Sorry, I don't have a minimal example yet, but I see this (and it's 100% reproducible) with one of my more complicated patches (https://bitbucket.org/agraef/raptor). The symptom is that none of the GUI elements in the GOP areas get updated any more. The patch works fine and I can even click the GUI elements in the GOP areas and hear that the patch responds to that but the display isn't updated at all.

The patch works fine in vanilla and in Purr Data up to 2.4.3, but in Purr Data 2.4.4 and later it is broken, so the bug got introduced somewhere on the road to 2.4.4.

@jwilkes, I vaguely recall that you did some GOP-related optimizations recently, maybe these are the culprit? Do you have any idea what commit might be causing this?