A new release of the Flask package (2.3.0, see https://flask.palletsprojects.com/en/2.3.x/changes/) removed the property session_cookie_name, which is still in use by INGInious frontend (inginious/frontend/flask/mongo_sessions.py). This is causing a frontend crash in every new installation of INGInious (from scratch), which installs the new Flask library as one of its dependencies.

INGInious installation details

• Version: 0.8.6 and earlier 0.8.x releases