TFW a BIOS update meant I couldn't boot my laptop...
Luckily I wrote some stuff down the last time it happened so it was a 3-minute fix. Boot off a USB, mount the drives and then run grub-install. 2 of the 3 minutes was spent looking for that USB stick with Ventoy on it that I knew I had laying around.
@graffen Oh yes, I've tried that. Not funny.
Also, another nice tip: Switching from UEFI boot to legacy boot in the firmware settings deletes your grub install too.