I have managed to reproduce this in a fresh lunar VM. Applied updates with update-manager, rebooted, ran the upgrade with update-manager -d. Rerunning 'snap install firmware-updater' from the commandline also fails, though not always with the same slot failing. Output of 'snap changes': ID Status Spawn Ready Summary 1 Done 2023-04-18 today at 16:54 PDT Initialize system state 2 Done today at 16:53 PDT today at 16:53 PDT Initialize device 3 Done today at 17:46 PDT today at 17:46 PDT Switch "core22" snap to channel "stable" 4 Error today at 17:46 PDT today at 17:46 PDT Install "firmware-updater" snap from "stable/ubuntu-23.10" channel 5 Done today at 17:46 PDT today at 17:46 PDT Switch "gnome-42-2204" snap to channel "stable/ubuntu-23.10" 6 Done today at 17:46 PDT today at 17:46 PDT Switch "gtk-common-themes" snap to channel "stable/ubuntu-23.10" 7 Done today at 17:46 PDT today at 17:46 PDT Switch "snap-store" snap to channel "stable/ubuntu-23.10" 8 Done today at 17:46 PDT today at 17:46 PDT Switch "snapd-desktop-integration" snap to channel "stable/ubuntu-23.10" 9 Done today at 17:46 PDT today at 17:46 PDT Switch "firefox" snap to channel "stable/ubuntu-23.10" 10 Error today at 17:51 PDT today at 17:51 PDT Install "firmware-updater" snap 11 Error today at 17:51 PDT today at 17:51 PDT Install "firmware-updater" snap output of 'snap tasks 4': Status Spawn Ready Summary Done today at 17:46 PDT today at 17:46 PDT Ensure prerequisites for "firmware-updater" are available Undone today at 17:46 PDT today at 17:46 PDT Download snap "firmware-updater" (109) from channel "stable/ubuntu-23.10" Done today at 17:46 PDT today at 17:46 PDT Fetch and check assertions for snap "firmware-updater" (109) Undone today at 17:46 PDT today at 17:46 PDT Mount snap "firmware-updater" (109) Undone today at 17:46 PDT today at 17:46 PDT Copy snap "firmware-updater" data Undone today at 17:46 PDT today at 17:46 PDT Setup snap "firmware-updater" (109) security profiles Undone today at 17:46 PDT today at 17:46 PDT Make snap "firmware-updater" (109) available to the system Error today at 17:46 PDT today at 17:46 PDT Automatically connect eligible plugs and slots of snap "firmware-updater" Hold today at 17:46 PDT today at 17:46 PDT Set automatic aliases for snap "firmware-updater" Hold today at 17:46 PDT today at 17:46 PDT Setup snap "firmware-updater" aliases Hold today at 17:46 PDT today at 17:46 PDT Run install hook of "firmware-updater" snap if present Hold today at 17:46 PDT today at 17:46 PDT Run default-configure hook of "firmware-updater" snap if present Hold today at 17:46 PDT today at 17:46 PDT Start snap "firmware-updater" (109) services Hold today at 17:46 PDT today at 17:46 PDT Run configure hook of "firmware-updater" snap if present Hold today at 17:46 PDT today at 17:46 PDT Run health check of "firmware-updater" snap ...................................................................... Automatically connect eligible plugs and slots of snap "firmware-updater" 2023-10-17T17:46:13-07:00 ERROR internal error: auto-connect of &{"firmware-updater:opengl" "snapd:opengl"} failed: snap "snapd" has no slot named "opengl" 'snap info snapd' shows installed: (18933) 0B broken The snap-snapd-18933.mount systemd unit claims everything is ok, but /snap/snapd/18933 is empty.