Reproduction steps:
1. Open project “EnumField.zip”
2. In the main menu click “Sample\SampleEditorWindow”
3. Enable and disable the “EnumField2 showMixedValue” toggle
Expected result: the EnumField turns back to its original value
Actual result: the UnumField remains a mixed string
Reproducible with: 2021.3.27f1, 2022.3.4f1, 2023.1.2f1, 2023.2.0a21
Reproducible on: macOS Ventura 13.2.1 (Intel)