Posted by maubot1112 on
URL: https://forum.librecad.org/right-mouse-button-tp5712877p5712966.html

I've found this page, in italian, very usefull for me:  http://www.lffl.org/2014/01/librecad-20-rilasciato-le-novita-e-come.html 
I've used:
sudo add-apt-repository ppa:librecad-dev/librecad-daily
sudo apt-get update
sudo apt-get install librecad