Re: [Trisquel-users] Mate-desktop

[davesamcdxv]

add-apt-repository is only for PPa.

For those lines: Open the terminal,
put deb http://packages.mate-desktop.org/repo/ubuntu precise main as one of  
the lines in the file caled /etc/apt/sources.list using a text editor

sudo apt-get update

Then install mate-archive-keyring (at this time all packages from the  
repository are "not authenticated", mate-archive-keyring serves to change  
that) , then sudo apt-get update again to make the MATE packages not "not  
authenticated".