For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:dmolkentin:netbox/openSUSE_Tumbleweed/home:dmolkentin:netbox.repo
zypper refresh
zypper install python-django-js-asset
For 15.4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:dmolkentin:netbox/15.4/home:dmolkentin:netbox.repo
zypper refresh
zypper install python-django-js-asset
For 15.3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:dmolkentin:netbox/15.3/home:dmolkentin:netbox.repo
zypper refresh
zypper install python-django-js-asset