I installed MX linux on a laptop I have, and added OpenSCAD, then I edited a file, and for test purposes did a copy/paste many times with no erroneous pastes occurring!  I think I have solved the problem and demonstrated that the problem is with the Cinnamon desktop.  8-(  I liked the way Cinnamon worked, and the shutdown timer that is one of the spices. Now I have to try installing the MATE desktop, and see if the problem goes away. Anyway, thanks for a very useful software. On 3/19/22 15:55, cogoman via Discuss wrote: > > Often I have a working model that needs a minor change. > > When I copy something from one location, and paste it into another > location, the editor ALSO pastes it into 2  or 3 random locations. I > find them when the preview fails and gives me a syntax error. > > Linux Mint 20 Cinnamon version 4.6.7 > > kernel                5.4.0-77-generic > > > OpenSCAD version 2019.05 >