"System.NullReferenceException" error is thrown when Generating Lighting with Adaptive Probe Volumes with Additive Scenes

Reproduction steps:
1. Open the “ReproProject“ project
2. Open the Lighting window (Window > Rendering > Lighting)
3. Press the “Generate Lighting” button in the Lighting window
4. Observe the Console window

Expected result: No errors are thrown in the Console window
Actual result: “System.NullReferenceException: Object reference not set to an instance of an object“ error is thrown in the Console window

Reproducible with: 6000.0.045f1, 6000.1.0b13, 6000.2.0a8
Couldn’t test with: 2021.3.36f1, 2022.3.60f1, 2023.2.16f1 (due to Adaptive Probe Volumes feature not existing)

Reproducible on: Windows 11 Pro (22H2), macOS 15.3.2 (M1 Max)
Not reproducible on: No other environment tested

Notes:

• Issue behaviour seems to vary between systems and Unity stream.

• • 6000.0, 6000.1 and 6000.2 throw a NullReferenceException if a scene is unloaded
  • 6000.0.45f1 has additional problems when baking with all scenes enabled. This breaks the Scene view and eventually leads to a crash