Since installing the new Lightroom version 3 days ago I'm having multiple issues with the app. I am unable to select masks (sky, subject and the new background). I have unistalled the app and reinstalled it twice and having the same problems.
Could you please share the system info of Lightroom (Help > About Lightroom> Copy-paste the details) and the version of Windows on your computer? What type of file are you working with? What happens when you try to use the features? Do you see any error messages?
Can you please disable the graphics processor? Go to Edit>Preferences>Performance. From theUse Graphics Processordrop-down menu, selectOff. Quit and relaunch Lightroom.