Ubuntu 20.04 Repo

Hi, Since upgrading to Ubuntu 20.04 (64bit, Mate) I've had trouble with the LibreCAD repo for updates. There's no Focal version, and that's ok, but "Stable main" does not work. When I use the command: sudo add-apt-repository ppa:librecad-dev/librecad-stable However when researching the subject it seems that updates come from the Ubuntu Universe repo. Also my version of LibreCAD seems up to date at 2.1.3 as of 2021-Apr-3. About the repository entry Under "Other Software" in the "Software & Updates" app, the Source entry with URI "http://ppa.launchpad.net/librecad/librecad-stable/ubuntu" Distrib: "stable" and Components: "main"; should this entry be removed? Thanks, Christian PS: I'm a long time user of AutoCAD 2D, IntelliCAD and others. The LibreCAD I/F is different and for a long time I dismissed it, but recently I found all it's capabilities and its GREAT !!! Thank you !!