gthumb from home:mantarimay:GNOME:apps project
Select Your Operating System
Add repository and install manually
For mantarimay run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:mantarimay:GNOME:apps/mantarimay/home:mantarimay:GNOME:apps.repo zypper refresh zypper install gthumb