Video Engine Won't Stay Disabled

[RTGraham]

I've just gone from 2019.6 to 2019.10 on a MacBook Pro (running Sierra), with some problematic side effects.

1) For one thing, it now seems impossible to keep the video engine disabled if I open a session containing video. We often separate the workloads to separate rigs, with one handling music / scoring, and a second handling video playback via sync (either satellite mode or else MTC/MMC over a network MIDI session).
So quite often, even though the "music" session contains a copy of the video, we keep the video engine disabled on that machine to avoid wasting RAM since the actual video display is from a separate machine. However, since installing 2019.10, if I open a session with video in it, Pro Tools automatically launches the video engine instead of asking whether I would like it enabled (as would happen in previous versions). So then I have to wait for the engine to launch, which sometimes it doesn't. Which brings us to point 2...

2) Quite often I work while mobile, using a MacBook Pro; and quite often I use a utility to force the machine to run only the integrated graphics chip instead of the more advanced discrete graphics chip, because the MBP's historically have issues with discrete graphics chips overheating, especially when using processor-intensive software like DAW's. Since installing 2019.10, the video engine (which previously worked even with the integrated chip) crashes unless I select the discrete chip.

3) Sessions with video that had previously opened correctly (under 2019.6) now *sometimes* give an error indicating that a codec is missing from the system. But not always. And they *sometimes* open with no checkmark on the video clip (meaning that it's not an Avid-sanctioned format) - but not always.

Has anyone else seen these kinds of issues under 2019.10?
Or is this all fairly unusual and I need to open a support ticket?

[Kit67]

I'm using 2023.6 on Mac. Everytime I open my project, Video Engine is enabled even though I had disabled it and saved it before.