Docker on OpenWRT, is this tutorial still valid?

Installing and Using OpenWrt
4

I plaxed around with docker according to Running PiHole on OpenWrt (x86/RPi) using Docker - Tutorial/Experiences


version: "3.3"

# More info at https://github.com/pi-hole/docker-pi-hole/ and https://docs.pi-hole.net/
services:
  pihole:
    container_name: pihole
    image: pihole/pihole:latest
    hostname: pihole
    environment:
       TZ: 'europa/zurich'
       WEBPASSWORD: 'RT67)IJN'
    # Volumes store your data between container upgrades
    volumes:
      - './pihole/etc-pihole/:/etc/pihole/'
      - './pihole/etc-dnsmasq.d/:/etc/dnsmasq.d/'
      - './pihole/var-log/:/var/log'
      - './pihole/etc-cont-init.d/10-fixroutes.sh:/etc/cont-init.d/10-fixroutes.sh'
    # Recommended but not required (DHCP needs NET_ADMIN)
    #   https://github.com/pi-hole/docker-pi-hole#note-on-capabilities
    cap_add:
      - NET_ADMIN
    restart: unless-stopped
#    ports:
#      - "53:535/tcp"
#      - "53:53/udp"
    networks:
      internal:
      lan:
        ipv4_address: 192.168.1.4

networks:
  internal:
  lan:
    name: lan
    driver: docker
    driver_opts:
      parent: docker0
    ipam:
      config:
        - subnet: 192.168.1.0/24
#   default:
#     name: docker

Now I get the error Plugin docker not found what does that mean?