How to reproduce:
1. Open the attached project "LightMapOffR.zip"
2. Open the "Scene" Scene
3. Open the Lighting window (Window > Rendering > Lighting)
4. Press the "Generate Lighting" button in the Scene tab
Expected result: The LIGHTMAP_ON variant is not selected for rendering
Actual result: The GameObjects appear black, indicating that LIGHTMAP_ON is still enabled but no lightmap is being read
Reproducible with: 2020.3.31, 2021.2.16f1, 2022.1.0b12, 2022.2.0a8
Could not test with: 2019.4.37f1 - due to errors in the Console window
Note: The shader is 'sabotaged' in order to make the keyword state more obvious with a color force to blue