nspirov

Thank you so much @codenixAU and @ahoeben! I have to rewrite my post, because it is not this option that helps, it is the resizing of the window. Even a 1-pixel resizing of the Cura window brings things back to normal. The option does help in a way, because not remembering the window position makes you resize it every time 🙂 Obviously this problem can have several different causes. `In my case - Catalina, Cura 4.13.1 - when opening Cura on the second screen (non-Retina resolution) it could not select objects, and also zoom and rotate behave strangely (with a huge offset in 3D space). After moving the window to the main screen (Retina), it resumes its normal behavior. However, you can make it work on the secondary screen as well, you just need to resize the window even one pixel and immediately everything goes back to normal again - selecting, zooming, rotating. I hope this helps.