S.O.O. is well known for bad URLs. Try a good one: https://cdn.opensuse.org/repositories/home:/ecsos/15.5/ https://cdn.opensuse.org/repositories/home:/ecsos/15.5/x86_64/grub-customizer-5.0.8-lp155.4.8.x86_64.rpm Next time you want to search, try opi instead.