(Pense à mettre tes retours entre balises Code.)
Il y a effectivement un problème, étant donné que tous tes dépôts sont passés en focal (20.04). Tu as essayé de relancer la mise à niveau à un moment ? Je t'avais donné un contenu corrigé avec les dépôts bionic (18.04), donc logiquement ils devraient être ok. C'est bizarre.
Quoi qu'il en soit, édite à nouveau ton sources.list :
sudo nano /etc/apt/sources.list
remplace son contenu par ça (bionic au lieu de focal partout) :
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://fr.archive.ubuntu.com/ubuntu/ bionic main restricted
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://fr.archive.ubuntu.com/ubuntu/ bionic-updates main restricted
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic-updates main restricted
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://fr.archive.ubuntu.com/ubuntu/ bionic universe
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic universe
deb http://fr.archive.ubuntu.com/ubuntu/ bionic-updates universe
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic-updates universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://fr.archive.ubuntu.com/ubuntu/ bionic multiverse
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic multiverse
deb http://fr.archive.ubuntu.com/ubuntu/ bionic-updates multiverse
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic-updates multiverse
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://fr.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse
# deb-src http://fr.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse
## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu bionic partner
# deb-src http://archive.canonical.com/ubuntu bionic partner
deb http://security.ubuntu.com/ubuntu bionic-security main restricted
# deb-src http://security.ubuntu.com/ubuntu bionic-security main restricted
deb http://security.ubuntu.com/ubuntu bionic-security universe
# deb-src http://security.ubuntu.com/ubuntu bionic-security universe
deb http://security.ubuntu.com/ubuntu bionic-security multiverse
# deb-src http://security.ubuntu.com/ubuntu bionic-security multiverse
puis enregistre : ctrl + O, valide le nom de fichier, ctrl + X.
Une fois que c'est fait, recharge les listes :
sudo apt-get update
et redonne la liste des paquets orphelins, qui devrait être bien moins longue :
apt list | grep "installé, local"