Here's what I had to set from a new empty project:
Switch project to Android
Add XR Plugin Management and check Oculus
Import Oculus integration v34 (I leave out the Sample Framework tree)
Remove the default camera and replace it with the OVRCameraRig prefab
Add an OVR PassthroughLayer script to the camera rig, and change "placement" from "Overlay" to "Underlay"
set Tracking orig Type to "Stage" so virtual objects stay in place in the real world despite orientation resets
check "Passthrough capability Enabled" and "Enable Passthrough"
In CenterEyeAnchor (in OVRCameraRig), change clear flags to "solid color" and set BG to black
In Player settings -> player:
set color space to Linear
change scripting backend to IL2CPP
uncheck "ARMv7" and check "ARM64"
... add your virtual objects, build to your Quest...
**bleep**. Thats quite the process, eh?