Steps to reproduce:

1. Create a new Unity project using the Universal 3D template
2. Make sure Hierarchy V2 is enabled
3. Create a new Scene (Assets > Create > Scene > Scene)
4. Drag the Scene to the Hierarchy V2 window
5. Right click the Scene and select "Unload Scene"
6. Double click the unloaded Scene
7. Observe the Console window

Actual results: "ArgumentException: SceneManager.SetActiveScene failed; scene 'New Scene' is not loaded and therefore cannot be set active" error is thrown

Expected results: No errors are thrown

Reproducible with versions: 6000.3.0f1, 6000.4.0b1, 6000.5.0a3

Can’t test with versions: 6000.0.64f1, 6000.2.15f1 (due to no Hierarchy V2)

Tested on (OS): MacOS M1 Silicon Tahoe 26.0.1

Notes:

• Does not reproduce with the old Hierarchy window