This container can be pulled via:
  docker pull registry.opensuse.org/home/dcassany/unifiedcore/tumbleweed/containers/k3s:1.35
  docker pull registry.opensuse.org/home/dcassany/unifiedcore/tumbleweed/containers/k3s:1.35_1.14-1.30

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.