How to reproduce:
1. Open the user’s attached “TestMaterialVariant.zip” project
2. In the Project window, select “simple Variant.mat” click three dots in the Inspector window of material, and select “Copy Material Properties”
3. In the Project window, select “simple Variant 1.mat” click three dots in the Inspector window of material, and select “Paste Material Properties”
4. Observe the material’s properties in the Inspector’s window

Expected result: Overridden properties text is highlighted as changed
Actual result: Overridden properties text is not highlighted as changed

Reproducible with: 2022.3.10f1, 2023.1.15f1, 2023.2.0b11, 2023.3.0a7
Could not test with: 2021.3.30f1 (Changes were not highlighted at all)

Reproduced on: macOS 13.5.2 (Intel)
Not reproducible on: No other environment tested

Note: if changing properties one by one in the Inspector window, then the issue is not reproducible