Gravity run cannot access lists after upgrade to v6

Thanks for the clarification.

Ok, so I figured out these two things myself. The dns argument affects the container itself. This was somehow not needed in v5 and I've never seen this before on any other docker compose file either. Anyways, using this solved my issue. Now everything works as expected again. Also regarding the DNS severs: there are simply several servers and it apparently doesn't hurt to use several of them I guess.

I'm still not sure what to do about the v5 environment variables that do not appear in the documentation or why I would add my local IP to the dns section.

But since everything is running well again I guess my issue was solved and I want to show my solution if anyone ever has the same issue. This is the working docker-compose.yaml (also includes information found out through later comments):

pihole:
    image: pihole/pihole:latest
    container_name: pihole
    ports:
      - "53:53/tcp"
      - "53:53/udp"
      - "80:80/tcp"
    environment:
      TZ: 'XXX'
      FTLCONF_webserver_api_password: ${PIHOLE_PW}
      FTLCONF_dns_listeningMode: "all"
      FTLCONF_dns_upstreams: "1.1.1.1;8.8.8.8;8.8.4.4"
    volumes:
      - './pihole/etc-pihole:/etc/pihole'
      - './pihole/etc-dnsmasq.d:/etc/dnsmasq.d'
    restart: unless-stopped
    dns:
      - "1.1.1.1"
      - "8.8.8.8"
      - "8.8.4.4"