How to reproduce:
1. Open the attached “IN-82791“ project
2. Press “Tools” → “Create Mesh and Prefab” from the Menu Bar to run custom script
3. In the Project window go to “Assets“ → “GeneratedAssets“
4. Select the “PrefabParent“
5. Observe the Inspector window - the “Mesh1” is assigned to ''Mesh”
6. Press “Tools” → “Create Mesh and Prefab”
7. Deselect and select the “PrefabParent“ again
8. Observe the Inspector window
Expected result: the “Mesh1“ is assigned to “Mesh“
Actual result: Mesh is “Missing (mesh)“
Reproducible with: 2022.1.0a7, 2022.3.44f1, 6000.0.17f1
Not reproducible with: 2021.3.43f1, 2022.1.0a6
Reproduced on: Windows 11, macOS 12.6.5 (Intel) (user)
Not reproduced on: No other environment tested
Note: Changing the name of the prefab makes the references appear as expected