macOS Catalina is finally here! If you’ve updated your Mac to version 10.15, we’ve got a few recommendations for you, besides having Catalina’s Golden Master version (not a beta) —
Duet must be able to capture the image in our virtual display to be able to send it to the mobile device at all. Prior to Catalina, the system that allowed us to run our virtual display was not tied to these permissions. Now with Catalina, Apple has tied these items together and that’s why allowing Duet in Screen Recording is required. To do so, on your Mac head towards System Preferences > Security and Privacy > Privacy > Screen Recording and checkmark Duet.
Duet must also be checked in Accessibility for touch to work – on your Mac go to System Preferences > Security and Privacy > Privacy > Accessibility and checkmark Duet.
If by any chance you’re not seeing Duet in Accessibility or Screen Recording, restart your Mac and try again – that should do the trick. If it’s still not showing, please submit a radar with Apple here using the Feedback Assistant as this is a known issue with macOS 10.15.