How to reproduce:
1. Open the “bug-netvis.zip“ project
2. Open the “SampleScene“
3. Disable “Domain Reload” in “Project Settings > Editor > Activate Enter Play Mode Options“
4. Enter Play Mode
5. Observe the Console not throwing any error
6. Exit and re-enter Play mode
7. Observe the Console

Expected result: No NullReferenceException error is logged
Actual result: A “NullReferenceException“ error is logged

Reproducible in: 2022.3.11f1, 2022.3.40f1, 6000.0.13f1
Not reproducible in: 2021.3.41f1, 2022.3.10f1

Reproduced on: MacOS 14.4.1 (M2)
Not reproduced on: Windows 10 (22H2), Windows 11 Pro (23H2)

Notes:
- The error reads: ”NullReferenceException: Object reference not set to an instance of an object”
- For the reproduction, the “Netcode for GameObjects” and “Multiplayer Tools” Packages are needed, but the root problem comes from within the Editor
- “Scene Reload” option does not impact the result
- In versions 2022.3.10f1 and 2022.3.11f1 two “ArgumentException: An item with the same key has already been added” errors are thrown either with or without the “NullReferenceException“