There is something very strange: it's already installed. If I run "apt policy grass-core" I have the text below.
I don't understand why it doesn't warn me when I try to install it. Sorry for the confusion and thank you very much for your time, I solved it grass-core: Installed: 7.8.0-1 Candidate: 7.8.3-1 Version table: 7.8.3-1 990 990 https://deb.debian.org/debian testing/main amd64 Packages 500 https://deb.debian.org/debian unstable/main amd64 Packages *** 7.8.0-1 100 100 /var/lib/dpkg/status 7.6.0-1 500 500 https://deb.debian.org/debian stable/main amd64 Packages -- Sent from: http://osgeo-org.1560.x6.nabble.com/Grass-Dev-f3991897.html _______________________________________________ grass-dev mailing list grass-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-dev