Attempt to change boot loader parameter results in shim-install fail

Brand new, erase-and-install, Leap 15.

Attempt to change boot loader parameter in YAST results in error message:

Execution of command ""/user/sbin/shim-install", "--config-file=/boot/grub2/grub.cfg"]]" failed.
Exit code: 5
Error output: Installing for x86_64-efi platform.
Installation finished. No error reported.
Could not prepare Boot variable: No space left on device

The “No space left on device” error doesn’t make sense since the /boot/efi partition is only 1% used.

Not everything that you do not understand does not make sense.

since the /boot/efi partition is only 1% used.
The message is not about /boot/efi. efibootmgr failed to create firmware BootXXXX variable that refers to newly created boot entry.

Try powering system completely down. Some firmware implementations are known to compress (defragment) space used to store variables only on boot. If it does not help it makes sense to boot some other distribution or live medium in case it is kernel issue.

Note that shim-install deletes old firmware bootmanager entry before creating new one. So it is possible that after power cycling system you will need to manually select correct file to boot. If you are not sure how to do it you may want to prepare something to boot from and repair boot configuration. Or prepare files in /boot/efi/EFI/Boot in advance in case firmware offers “EFI boot from disk” option.

No improvement.