This seems to be happening on TestFlight builds on macOS 15 beta 3. Feedback submitted: FB14288230

Thanks for bringing this up @LocalWE and thanks for the informative answer @DTS Engineer. The path forward is clear for macOS 15 and App Store distribution but if I understand correctly implementing the app groups that way group.* would prevent supporting app groups on macOS 14, is that right?

That's a good idea. I just tried doing just that using beta 3. The barebones test app correctly shows the AR camera capture interface. The LockedCameraCaptureExtension also works fine (except it cannot render the AR elements) if I comment out the ARSCNView from my view finder interface. That's I think the cause of the error is my ARSCNView. Is it not allowed to use an ARSCNView in a LockedCameraCaptureExtension?