My common solution to boot issues that lock me out is,

1. Get a USB Live distro (always good to have a backup lying around)

2. Boot into live distro

3. Chroot into the broken distro (Arch wiki has an article on this)

4. Fix any bugs that I can find and/or reinstall the bootloader

5. Test, repeat until the problem has been found and fixed

Hope it helps any newcomers!

Cool! I’d love to see what custom microcode comes of this. Especially in relation to the speculated backdoors on CPUs