Can't login on CAIRIS on local docker without Internet connection

[Landsp]

Expected behaviour

Login to CAIRIS in docker environment on local machine, without Internet connection

Actual behaviour

I have an docker setup of CAIRIS on a local Ubuntu machine. It's working as expected. But If I don't have Internet connection from the docker, I can't login.
Edit I'm working from the desktop on the local machine with the docker environment.

Steps to reproduce the behaviour

I have tried the following:

Login without Internet connection
Login screen is there but can´t authenticate and get past the login screen

Login with Internet connection and then directly disable connection to Internet
Login is working and I can after that continue to work with disconnected interface to Internet

Findings and Conclusion

Everything is working without Internet connection except during authentication.
After doing a simple scan of the Internet traffic. The only thing I could see, was that CAIRIS tried to connect to TRELLO during the login phase.
Comment: I was doing a very simple scan of the outgoing traffic and can be wrong. It looks like it was to an Atlassian owned IP address. I assumed it was to TRELLO sinse integration to TRELLO is possible.

Version of CAIRIS

Latest docker. See date in ticket.

Details of browser or, if applicable, details of the OS used to host CAIRIS

Firefox, Chrome on Ubuntu 22:04 LTS
I have tried SNAP install of docker and Docker Engine from "docker".
I'm not working with TRELLO and wish to use CAIRIS for educational purpose on a closed virtual machine or locked down network.

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