How to reproduce:
1. Open the attached project "case_1331034-GizmoTest.zip"
2. Open SampleScene
3. Click on GameObject in the Scene Hierarchy
4. Expand the GizmoTest script in the Inspector
5. Observe the messages printed to the Console
6. Collapse the GizmoTest script
7. Observe nothing is printed to the Console
8. Close and reopen the project
9. Observe messages printed to the Console

Expected result: No messages are printed to the Console after reopening the Project
Actual result: Messages are printed to the Console despite the GizmoTest script being collapsed

Reproducible with: 2018.4.34f1, 2019.4.25f1, 2020.3.6f1, 2021.1.5f1, 2021.2.0a15

Notes:
1. If you expand and collapse the GizmoTest script after restarting the Editor the OnDrawGizmos method will not be called any more