Difficulties upgrading 2018 mac mini from 15.7.5 -> 15.7.7

[djc6]

tl;dr - consider unplug all unnecessary hardware before updating.

I updated my 2018 mac mini running 15.7.5 to 15.7.7 and had some issues after the installer began. It rebooted the machine, then I would see apple logo with progress bar. Machine would abruptly shut off. Then it would show the status bar again, etc.. eventually it powered off and stayed off. I then turned it on, and it did this loop again - but once threw in a kernel panic (multilingual "You need to restart your computer" screen).

I was only finally able to get it to boot by unplugging all accessories except power, keyboard, mouse and monitor - no network, owc thunderbay 4, usb-c hubs, etc..

Finally the update completed, I plugged everything back in, things are fine once again.

Claude had this to say when I gave it the /Library/Logs/DiagnosticReports/ProxiedDevice-Bridge/panic-full-2026-05-12-015822.0003.ips kernel panic crash report:

The XNU kernel panicked in imageboot.c at line 1095 because it could not authenticate and mount x86_64SURamDisk.dmg (error 19, ENODEV — device not found), meaning the RAM-backed block device the updater had set up was gone by the time the kernel tried to mount it as root.