I know, I’m the insane person for using an unsupported distro, but I get an error that seems pretty universal when I attempt to update using fwupdmgr:
/boot/efi does not have sufficient space, required 93.2 MB, got 67.1 MB
Do I have to switch to Fedora briefly to get this firmware update installed?
EDIT: now fwudpmgr won’t even let me retry the failed firmware update. What do I do, install Windows 11 so I can do updates properly?
Your EFI system partition is too small or has too much stuff on it. Clear up some space or make a bigger one
I managed to update the firmware using the UEFI Shell update, although that had its own gotchas (the directions do not mention that you have to put up the boot flag in order to boot from the fat32 partition, nor that the partition becomes read only once you do).
That being said, how would I make a bigger EFI system partition and then set that as the UEFI partition to boot from? It sounds like the easiest way to sidestep the whole rigamarole I had to go through with the UEFI Shell update.
EDIT: whoops, forgot to mention I got the prebuilt version, mostly to avoid the stress of potentially messing up on installing the RAM and SSD. This was the first time I assembled anything.
Basically boot a live USB key and delete/resize other partitions and make a new one using a partition editing tool.
Yup. Just make sure you copy all the stuff off the old one before you delete it 
Well, I’ve done something horrible and somehow managed to resize the existing EFI partition to 500 MB (which according to openSUSE should be more than enough) even though gparted claimed it couldn’t resize it. And yet, so far, everything still seems to function.
If it all comes crashing down upon the next firmware update, meh, I’m on btrfs, constant backups are going to be a fact of life for me. Also, I haven’t migrated all my user data off my Steam Deck yet, so no harm, no foul. Just going to have to reinstall again, which was mostly painless anyway.
Actually, I just nuked the entire hard drive off the face of the planet and reinstalled Tumbleweed, only took 15 minutes to get back to where I was.
Should’ve done this from the get-go.