Comment # 9 on bug 1121179 from Chester Lin

Updating my findings:

1. As Lubos said, the installation media of Tumbleweed works fine with UEFI
secure boot.

2. I tried Steffen's suggestion to make a specific leap 15.0 iso with replaced
grub.efi copied from Tumbleweed, and it can run from UEFI secure boot
successfully.

It should be a compatible issue but now we have workaround solutions as above.