This container can be pulled via:
  docker pull registry.opensuse.org/opensuse/stunnel:5
  docker pull registry.opensuse.org/opensuse/stunnel:5.77
  docker pull registry.opensuse.org/opensuse/stunnel:5.77-10.146
  docker pull registry.opensuse.org/opensuse/stunnel:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.