Reproduction steps:
1. WARNING: save any unsaved data as after reproducing this you will need to restart your PC
2. Open project in "New Unity Project.zip"
3. Open SampleScene and enter Play Mode
4. Press quit on the Fatal Error window
5. Access from developer tools will be requested (can take up to 20 seconds)
6. Give access by entering the password (read Note 1)

Unexpected behaviour: Unity will freeze and will not respond to Force Quit requests (read Note 1)

Reproducible with: 2018.2.22f1, 2019.3.14f1, 2020.1.0a18
Not reproducible with: 2020.1.0b8, 2020.2.0a12, 2020.1.0a19 -> fix version

Tested with iMac Catalina 10.15.3

Notes:
1. If you choose to not give access for Developer Tools Access, it will be requested again and again for 4-5 (sometimes more) before Unity quits (sometimes it doesn't and stays frozen). At this point, you can still force quit the application.
2. This reproduces with all Fatal Errors
3. Video attached shows the issue after entering the password (OBS crashes along with Unity)