How to reproduce:
1. Open the attached “IN-134857” project
2. Open the “MainMenuManager” prefab from the Project window
3. In the Inspector change a value from “MainMenuManager.cs”
4. Save the prefab
5. Observe the Console window

Actual result: “Unsupported type” error gets thrown
Expected result: No errors are thrown

Reproducible with: 2023.3.0a15, 6000.0.68f1, 6000.3.10f1, 6000.4.0b10, 6000.5.0a7
Could not test with: 2023.3.0a14 (Multiple errors from third-party packages)

Reproducible on: MacOS Sequoia 15.7.3 (M1 Max)
Not reproducible on: No other environments tested