Collaboration not working inside file but works in terminal.

[Antoine Delègue]

Description

While I can see cursors and selections of other people, the file is not saved automatically and I cannot see what other users are typing. I does not work for notebooks or plain text files.
When using a terminal however, collaboration works properly.

Reproduce

I'm using the following docker-compose.yml file:

services:
  jupyter:
    image:  jupyter/pyspark-notebook:latest
    restart: unless-stopped
    ports:
      - "8888:8888"
    user: root
    working_dir: /home/vanyle
    environment:
      - NB_USER=vanyle
      - CHOWN_HOME=yes
    command: "start-notebook.py --ServerApp.token='' --ServerApp.password=''"
    volumes:
      - ./models:/home/vanyle/work

When the docker is started, I manually install jupyter_collaboration and I restart the docker.

Expected behavior

I would expect jupyter-collaboration to work. When a character is typed on one device, it appears on the other.

Context

• Operating System: The issue occurs on all OS I tested, including Windows 11 and MacOS (meaning the docker is executed inside MacOS / inside Windows).
• Browser and version: The issue arises on all browser I tested, including Firefox, Edge and Chrome.
• JupyterLab version: 4.1.4
• Jupyter collaboration version: 2.0.3

I have the following plugins installed:

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[David Brochart]

What do you mean by "works in terminal"?

[David Brochart]

I'm facing the issue, it seems to be caused by pycrdt v0.8.13.
Could you pip install "pycrdt<0.8.13" and see if it solves your issue?
I'll investigate what is wrong in pycrdt.

[David Brochart]

I yanked pycrdt v0.8.13 on PyPI, marked it as broken on conda-forge, and released v0.8.15 with a fix.

[Antoine Delègue]

It works! Thank you! I spend like 2 hours tweaking the configuration of my docker (as I'm using a custom docker with a lot of extensions) and nothing was working.

Just out of curiosity, what was the issue with pycrdt ?

[David Brochart]

In pycrdt v0.8.13 the Rust backend Yrs was updated to v0.18, which changed the way observer subscriptions are handled. Now instead of getting a subscription ID, a subscription object is returned, and unobserving is done by dropping the object, so in Python a reference to the subscription has to be kept, otherwise it gets garbage-collected and it is dropped on the Rust side (see y-crdt/y-crdt#398).
I had done that for shared types in jupyter-server/pycrdt#85 but I forgot to do it for docs, and that's now fixed in jupyter-server/pycrdt#87.
Basically all this means is that the changes to a document in JupterLab was not propagated to other users.