diff --git a/jupyterlab/labapp.py b/jupyterlab/labapp.py index 8de707642bb7..34d77b0a34ef 100644 --- a/jupyterlab/labapp.py +++ b/jupyterlab/labapp.py @@ -897,13 +897,15 @@ def initialize(self, argv=None): import jupyter_collaboration # noqa except ImportError: self.log.critical( - """ + """\ +Juptyer Lab cannot start, because `jupyter_collaboration` was configured but cannot be `import`ed. + To enable real-time collaboration, you must install the extension `jupyter_collaboration`. You can install it using pip for example: python -m pip install jupyter_collaboration -This flag is now deprecated and will be removed in JupyterLab v5. +To run without collaboration, disable collaboration (for example, remove the `--collaborative` flag from the commandline; this flag is now deprecated and will be removed in JupyterLab v5). To see more ways to adjust the collaborative behavior, see https://jupyterlab-realtime-collaboration.readthedocs.io/en/latest/configuration.html and https://discourse.jupyter.org/t/how-to-disable-jupyter-collaboration-extension/21329/9 . """ ) sys.exit(1)