yes, and the problem is that there are two grub.cfg files: /boot/efi/EFI/boot/grub.cfg /boot/efi/EFI/opensuse/grub.cfg and the /boot/efi/EFI/boot/grub.cfg was garbage for some reason. Running update-bootloader did not fix the problem, only copying /boot/efi/EFI/opensuse/grub.cfg to /boot/efi/EFI/boot/ by hand.