Objects in the non-active scene are not spawned when starting NetworkManager as host

Steps to reproduce:

1. Open the attached “IN-147648” project
2. Open the Assets/_Scenes/Startup.unity scene
3. Enter Play mode
4. Press the "PLAY" button
5. Press the "Create Save" button
6. Enter any name under "Enter save name"
7. Press the "Play" button
8. Press the "Ready up" button
9. Observe the RpcException due to the "GameManager" object not being spawned (Look in DontDestroyOnLoad/GameManager)

Actual result: The NetworkManger doesn't spawn the GameManager NetworkObject
Expected result: The NetworkManager spawns the GameManager NetworkObject

Reproducible with: 2.13.0 (6000.5.1f1)
Not reproducible with: 2.12.0 (6000.5.1f1)

Reproducible on: Fedora Linux 44 (By reporter)
Not reproducible on: No other environments tested