I wouldn’t necessarily call this one solved, but I “chroot” using the latest USB image and backed up my home folder. Formatted and re-installed from scratch. Wasn’t all that bad, but I didn’t get a chance to export my Vivaldi passwords and Kwallet. Next time I’m going to export the wallet monthly.
In the end, my video card might be the problem, as I cannot install any version of the Nvidia driver without getting a black screen. Fixed by uninstalling the driver and sticking with Nouveau.
For future users who run into this same issue. Perhaps try everything that was suggested before re-installing. Your mileage will certainly vary and something on these posts might work for you.
Breaking and fixing is part of the adventure. Onto breaking the next update!
Thanks to all who tried to help. Much appreciated.