Ubuntu Wifi ICE and Docker
Running Docker on a Linux computer may cause connectivity issues in a German ICE train. If you are not able to enter the captive portal (https://login.wifionice.de), try to delete the docker network temporarily (sure not being able to use Docker then).
sh
sudo ip -4 addr del 172.18.0.1/16 dev br-...
Dont know if this works on Windows though...