Lister les paquets locaux ou obsolète d’une distribution GNU+Linux basées sur Debian
$ sudo apt install apt-show-versions
$ apt-show-versions | grep -v buster (1)
$ apt-show-versions | grep -v buster | awk '{print $1}' | xargs apt remove (2) (3)
1 | List all packages and remove those with buster in the line, so belonging to the current stable version of Debian |
2 | Selecting, in addition, the 1st column and apply apt remove on each result |
This will also remove the local packages, that where never part of the official distribution. |