ICE-Wifi is using the same IP-address scope as the first docker-container (172.18...) so WIFI is not working. To change the docker defaults and remove the existing container-network follow these steps:
sudo nano /etc/docker/daemon.json
add:
{
"default-address-pools":
[
{"base":"172.27.0.0/16","size":24}
]
}
sudo service docker restart
sudo docker stop CONTAINER-NAME
sudo docker network prune
Now reconnect wifi and open http://wifionice.de/