I noticed this with my own app and other Unity fully immersive apps on the app store. If user opens Vision OS control center by looking up and tap while in the immersive app, the immersive app closes it self after a few seconds of keeping the control center open. Then users have to relaunch the app and start from the beginning.
I am not sure if it’s a feature or a bug, but is there a way to keep the app running while control center is open?
Probably a feature as Apple seems to hate us VR (or “fully immersive”) devs. Haha
jk of course. I’m sure Apple loves us just as much as the MR devs.
We are seeing similar behavior where opening the control center freezes the Unity VR app, and then triggers the “headlocked content” warning. However, it does not kill or crash the app.
Is there a way to configure the permissions or XR Rig such that the content keeps rendering even when control center is open?
Did some googling and found another post asking about the same problem! App Crashes when Opening Control Center - #17 by diegovis
The solution mentioned in that post works for me for both fixing the crash and prevent head-lock. But it introduces re-center issues 
Hope that Unity can expose callback for opening control center and entering home screen on VisionOS soon.