We need our program to continue rendering the camera, even if the oculus is unmounted.
Before this was possible with run in background, and additionally having listeners on the mount / unmount events that manually disabled the UnityEngine.XR settings - this took care of the wrong aspect ratio once the headset was unmounted.
Now in 2017.4 (moved from 2017.1 i think) the screen is just black once the headset is removed.
The hard part is to pinpoint the source of the problem - either oculus utilities for unity or unity xr itself…
Anyone has ideas?