Reproduction steps:
1. Create a new project
2. Install Multiplayer Play Mode package (Window > Package Management > Package Manager)
3. Open the Play Mode Scenarios window (Window > Play Mode > Scenarios), add a new Scenario and an additional Editor Instance
4. Select the newly created Scenario as the active Scenario and enter Play mode
5. Enable Hierarchy and Inspector windows in the Layout menu of Player 2 window
6. Create a 3D GameObject (e.g. + > 3D Object > Cylinder)
7. Add a Material to the Mesh Renderer component of the newly created GameObject in the Inspector
8. Observe the Console
Actual result: "AssertionException: Assertion failure. Value was False" error and memory leak warnings are thrown
Expected result: No errors or warnings are thrown
Reproducible with: 3.0.0 (6000.6.0b4, 6000.7.0a2)
Not reproducible with: 1.6.3 (6000.0.79f1), 2.0.2 (6000.3.20f1, 6000.5.4f1)
Reproduced on: Windows 11, macOS Tahoe 26.5 (M4)
Note: Issue is not reproducible if “Use Proxy Volume” is set in Mesh Renderer Light Probes setting