I do not know which forum to put this. I have 4.23. I recently updated my Mac to OS Catalina. Now launching the editor is problematic at best. I use to be able to click on a .uproject file and it would take a bit of time, but it would always open. Now, the project does not usually open, or I get the ‘Unreal Project Browser’ which has no projects listed. Or, the editor opens showing a blank project.