This container can be pulled via:
  docker pull registry.opensuse.org/devel/bci/sle-15-sp6/containerfile/suse/kiosk-firefox-esr:128.9
  docker pull registry.opensuse.org/devel/bci/sle-15-sp6/containerfile/suse/kiosk-firefox-esr:128.9-48.8
  docker pull registry.opensuse.org/devel/bci/sle-15-sp6/containerfile/suse/kiosk-firefox-esr:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.