What problem? Exactly what does “does not boot” mean? Power turns off when you make the default Grub selection? Cooling fans howl? Can you login remotely? Does it happen every boot? Does SDDM come up, but not let you login? Do you have automatic login enabled?
Do you get a login prompt on a black screen? My first boot with i5-11400 produced this result. Logging in as root on vtty3 and running systemctl restart xdm brought up the login greeter. 4 subsequent 5.19.12 boots have worked as expected:
After 10 minutes we can’t make any needed edits. You replied to what was intended as a correction to my post #2 here. 5.19.12 booted just fine, just not directly into X on first boot after installing 5.19.12. Other forums don’t have the 10 minute cutoff, and misleading material can be corrected at any time.
today, I also installed kernel 5.19.12 on a Lenovo Thinkpad Carbon X1 (9th Gen). The computer booted well with the new kernel, but when plugging the external monitor everything becomes black. It was only possible to switch out the computer and restart it.
After trying two times to plug the monitor, I switched back to kernel 5.19.10 and everything is working fine.