There are known issues with some distributions of Linux, we recommend using Ubuntu 18.04 or 16.04
The command we use to set up the custom protocol handler for Classroom Assistant fails on some distros.
You can try setting it manually by running:
xdg-settings set default-url-scheme-handler x-github-classroom classroom-assistant.desktop
For XFCE based desktops, xdg-settings does not seem to work, you have to manually set up the protocol handling for the application to work.
The package we use for storing tokens on Linux needs an additional dependency on KDE. This can be installed with
sudo apt-get install gnome-keyring