Reproduction steps:
1. Open the attached project "ReproProj"
2. Open the “/Assets/Scenes/SampleScene.unity” Scene
3. Enter the Play Mode
4. Open the Frame Debugger (Window > Analysis > FrameDebugger)
5. Click “Enable”
6. Select Secondary Camera
7. Observe the Output

Expected result: Scene and GameObjects are present in the Output
Actual result: Output is grey

Reproducible with: 2022.3.31f1, 6000.0.4f1
Could not test with: 2021.3.39f1 (Packages\com.unity.collections\Unity.Collections\FixedList.gen.cs(23,13): error CS0234: The type or namespace name 'Properties' does not exist in the namespace 'Unity')

Reproducible on:
VLNQA00379, Oculus (Quest 2), Android 10, CPU: Snapdragon XR2, GPU: Adreno (TM) 650

Testing environment: Windows 10 Enterprise 21H2
Not reproducible on: No other environment tested

Notes:
- Does not reproduce if VR is not connected
- Reproducible with Oculus XR and OpenXR
- Render texture is also grey (In Hierarch select XRRig > Camera Offset > Main Camera > Secondary Camera and in Inspector, double click on the camera's output texture)