Multi-os menu disabled in Android Studio

[Noisyfox]

See my comments in this thread

Failed to populate list of simulators

After I installed Xcode beta 11, I got this error “Failed to populate list of simulators”. Then I uninstall Xcode beta 11 and now only have Xcode 10.3 and the command-line tool is already installed. But I still get that error. How can I fix it? Thank you.