Most users don’t need it. Get rid of it: After a shim update yesterday, no longer able to boot with secure boot enabled - #23 by karlmistelberger
Stay with UEFI. Turn off Compatibility Support Module. Use default partitioning. The openSUSE installer suggests for empty disks:
3400G:~ # fdisk -l /dev/nvme0n1
Disk /dev/nvme0n1: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: Samsung SSD 950 PRO 512GB
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: A84F222E-0177-499B-A7EA-BDA6F31E2196
Device Start End Sectors Size Type
/dev/nvme0n1p1 2048 206847 204800 100M EFI System
/dev/nvme0n1p2 206848 1000214527 1000007680 476.8G Linux filesystem
3400G:~ #
3400G:~ # lsblk -f /dev/nvme0n1
NAME FSTYPE FSVER LABEL UUID FSAVAIL FSUSE% MOUNTPOINTS
nvme0n1
├─nvme0n1p1 vfat FAT16 6DEC-64F9 97.4M 2% /boot/efi
└─nvme0n1p2 btrfs tumbleweed-nvme0n1p2 e7ad401f-4f60-42ff-a07e-f54372bc1dbc 289G 39% /var
/home
/opt
/root
/usr/local
/srv
/boot/grub2/x86_64-efi
/boot/grub2/i386-pc
/.snapshots
/
3400G:~ #