How to reproduce:
1. Open the project attached by the user (PreviewTest.zip)
2. Open scene "Scene A"
3. Open the "GameObject Editor" window, drag the "Cube" Prefab to it
4. Open scene "Scene B"
5. Observe the "Cube" Prefab change lighting in the GameObject Editor window

Expected result: Lighting on the Prefab updates without needing to switch Scenes
Actual result: To update the lighting on the Prefab, switching Scenes is necessary

Reproducible with: 2017.1.0f1, 2017.1.4f1, 2017.2.3f1, 2017.4.4f1, 2018.1.2f1, 2018.2.0b5
Not reproducible with: 2017.1.0a1, 2017.1.0b10

Notes: The script which enables the GameObject Editor window can be found here: https://docs.unity3d.com/ScriptReference/Editor.OnPreviewGUI.html