Back when I used ubuntu, Unity was stuck with old gnome packages. This meant that the version gnome-terminal packaged with ubuntu (up to at least 18.04) didn’t have text reflow on window size changes.
You could add the upstream sources, upgrade the specific text reflow package only, and then disable the sources.
I forgot to disable the sources, or typed dist-upgrade (this happened multiple times…). Broke the whole desktop/lightdm setup with half upgraded packages, and half removed packages (for preparation to install new versions). Way easier to reinstall the os than to disentangle. Unity was a mess then anyway.
Moral: Actually read the package change summaries when doing updates/removes/installs, and [ y/N ] means actually check what the fuck you think you’re agreeing to.
BtrFS snapshots for idiots
I’ve also run automated snapshots on my btrfs partition, then run out of space doing multi-hop system upgrade on fedora (dnf has a plugin that creates a snapshot every time it kicks in.
You can imagine there were many changes happenning per snapshot, and I effectively could have rolled back 4 major fedora versions… Til I ran out of space.
I couldn’t get a replacement drive in time, and I had an hour to rebuild my laptop before needing to be on a customer site, so sadly I couldn’t preserve my drive for later investigation. My best guess is the high-water-mark was configured incorrectly, and somehow it was able to ‘write’ data past the extents of the filesystem.
Rollback did work for my home partition, but I had to mount it from another OS to get it to work - so no data loss!
By that time I’d already reinstalled the os to the root partition/subvolume however, so I couldn’t determine the exact cause of failure :(
Moral: Snapshots are not backups, and ‘working’ is not ‘tested’
You might check your BIOS clock time too, if the certs are ‘expired’, it might be the future, or more likely, the past. Certs have validity timers that specify start and end.
It’s more likely that your BIOS is just old, and you’ll have to keep secure boot disabled from now on.