How to reproduce:
1. Open the attached "case_1379559.zip" project
2. Open the "SampleScene" Scene
3. Open the HighlighterTest window (Bug > HighlighterTest) and dock it together with the Project window
4. Select the "Directional Light" GameObject in the Hierarchy
5. Make sure that the "Rigidbody 2D" Component is visible in the Inspector
6. Press "Start Highlight" in the HighlighterTest window
7. Press on empty space in the Hierarchy
Expected result: The highlight disappears
Actual result: The highlight does not disappear
Reproducible with: 2019.4.33f1, 2020.3.24f1, 2021.2.5f1, 2022.1.0a16
Note:
- Not reproducible on macOS
- The highlight disappears after closing the window where the highlighted element is
- The highlight disappears after entering Play mode