Watchtower

version: "3.3"
services:
    watchtower:
        image: containrrr/watchtower
        container_name: watchtower
        volumes:
            - /var/run/docker.sock:/var/run/docker.sock
        environment:
            - TZ=Europe/Paris
            - WATCHTOWER_MONITOR_ONLY=true
            - WATCHTOWER_SCHEDULE=0 0 10 ? * SAT
            - WATCHTOWER_CLEANUP=true
           # - WATCHTOWER_NOTIFICATIONS=email
           # - WATCHTOWER_NOTIFICATION_EMAIL_FROM=contact@s.com
           # - WATCHTOWER_NOTIFICATION_EMAIL_TO=t@free.fr
           # - WATCHTOWER_NOTIFICATION_EMAIL_SERVER=ssl0.ovh.net
           # - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_PASSWORD=xxxxxxxx
           # - WATCHTOWER_NOTIFICATION_EMAIL_SUBJECTTAG=RPi4
           # - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_USER=contact@s.com
           # - WATCHTOWER_NOTIFICATION_EMAIL_SERVER_PORT=587
            - WATCHTOWER_NOTIFICATIONS=shoutrrr
            - WATCHTOWER_NOTIFICATION_URL=discord://web_hooooooooookweb_hooooooooook/slack
        restart: unless-stopped

Check once :

docker run --rm -v /var/run/docker.sock:/var/run/docker.sock containrrr/watchtower --run-once

Discord notif: https://containrrr.dev/shoutrrr/v0.5/services/discord/

Image name problem : https://github.com/containrrr/watchtower/issues/1050#issuecomment-968309913