So, The weirdest thing happened to me...
I got a problem with not being able to option click a source file to open it next to the source file I'm working on.
Weird.... So, I booted back into my pre-catalina OS, and tested there. Option click works there.
So, back to Catalina beta. Created a new user account. Switched to that account, started xcode, created a new project and voila. Option click works. I thought I knew the fix: Use the new user account and work from there. So I open the project I was working on and...... No more option click to open a source file next to another source file.
So, on the same machine, same partition, same XCode, same XCode settings (!!!), I can use option clicking in projectONE on source files to open them next to the active editor, but not on projectTWO.
What could be the problem?
Xcode 11: Option click on source file does not open in next editor
You probably already figured it out, but when it was happening to me it turned out I had split view editors with one of the editors being in focused mode (top-left corner arrows icon), so I couldn't see the other one. In that mode option-click doesn't do anything.
Thank you!!! Hunting down this issue was driving me mad!