After release upgrade problems with snapd on another installation

[BertN45]

I had to use a VM to report the bug, because the involved systems did not support ubuntu-bug anymore.
Yesterday I had two systems on two disks;
- one main installation of Ubuntu 23.10 on a 512GB nvme using OpenZFS as boot file system.
- one backup ext4 installation of Ubuntu 22.04 LTS on a 19GB partition on a HDD.
I had the stupid idea to upgrade 22.04 LTS to 24.04 with "do-release-upgrade -d". The upgrade did run into some free-space issues, but it finished and it more or less worked. I had to fiddle with the installed snaps, but in the end also those worked after a lot of "snap refresh --ignore-validation". My bug is not related to this installation. I will restore 22.04 from an backup image :)

Unfortunately in the other main installation snaps stopped working. The main installation is a minimal install, so normally I only use Firefox and Virtualbox to start the VMs with all my Apps. The whole snap subs-system is in great chaos and it can't decide whether firefox is installed yes or no. The attachment shows the reaction of the system after a fresh boot trying to use firefox and following your automated advises. I also re-installed snapd and even tried to remove everything related to snaps, but nothing helps. It looks like a central Canonical snap database confuses both installations on the same system but different disks.

I have two options;
- I reinstall everything on the 512GB nvme-SSD, a lot of work even when restoring from backups.
- I ignore firefox and install MS-Edge from a deb I have lying around and wait for a correction of the error or if needed on the official 24.04 LTS release :)

ProblemType: Bug
DistroRelease: Ubuntu 23.10
Package: ubuntu-release-upgrader-core 1:23.10.14
ProcVersionSignature: Ubuntu 6.5.0-14.14-generic 6.5.3
Uname: Linux 6.5.0-14-generic x86_64
ApportVersion: 2.27.0-0ubuntu5
Architecture: amd64
CasperMD5CheckResult: pass
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Wed Dec 20 09:22:39 2023
InstallationDate: Installed on 2023-05-07 (227 days ago)
InstallationMedia: Ubuntu 23.10 "Mantic Minotaur" - Daily amd64 (20230506)
PackageArchitecture: all
ProcEnviron:
 LANG=en_US.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 TERM=xterm-256color
 XDG_RUNTIME_DIR=<set>
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: No upgrade log present (probably fresh install)
VarLogDistupgradeTermlog: