openSUSE-Addon-NonOss-release from openSUSE:Leap:15.6:Update project
Select Your Operating System
Add repository and install manually
For standard run the following as root:
zypper addrepo https://download.opensuse.org/repositories/openSUSE:Leap:15.6:Update/standard/openSUSE:Leap:15.6:Update.repo zypper refresh zypper install openSUSE-Addon-NonOss-release