Hi I would like to use Pre-Depends in the cadabra2 packge so it'll not break the jupyterhub notebook. It gets broken due to the package python3-notebook creating a symlink for the codemirror at /usr/lib/python3/dist-packages/notebook/static/components Now if cadabra2 which puts a part into that directory, while it's not yet symlinked the codeeditor part of notebook gets broken. If someone has a better solution please tell so. Best, Alex