Scrolling over notebook got unexpected jump backs

[AllanChain]

Description

With jupyterlab-myst installed, scrolling over the notebook is not smooth. Specifically, when I try to scroll up, it can sometimes jump back, and I have to scroll multiple times to get to the place I want. Like the following screen recording:

Kooha-2024-06-14-21-56-28.mp4

Without jupyterlab-myst installed, I can scroll smoothly without issue.

Reproduction steps:

1. Create a new venv

2. Install jupyterlab and jupyterlab-myst

3. Launch JLab and create a notebook

4. Put something in and make it scrollable

5. Scroll to the bottom and slowly scrolling up

Proposed solution

Sorry, I don't have any idea what's causing this issue.

Additional notes

Maybe it is related to jupyterlab/jupyterlab#15795, but I can't reproduce that issue without jupyterlab-myst installed.

Environment:

• Browser: Firefox and Chromium
• JupyterLab: 4.2.2
• jupyterlab-myst: 2.4.2

[agoose77]

Thanks for this report. Looks like it might be a performance issue of some kind. I'll dig in to this.

[krassowski]

I can reproduce this. Related to jupyterlab/jupyterlab#16326

The problem is that myst changes height of the cell after it is attached; this pushes the viewport down, which in turns detaches the cell, preventing user from scrolling up. There may be a way to fix it upstream in JupyterLab.

In the meantime a simple solution would be to cache the rendered content so that it is shown immediately when cell gets attached. It seems that the markdown cells when rendered with myst start from a blank state and are populated afterwards.

To make it easier to reproduce I would suggest using a markdown cell with admonition and a mermaid diagram.

[earlbellinger]

Having recently developed course materials using jupyterlab-myst, I am experiencing this bug quite frequently. I hope this can be resolved!

[nthiery]

Same here; it's been one of the main UI annoyances that was reported by our students.

[psychemedia]

I'm also trying to push MyST in notebooks but if the myst extension is the one upsetting notebook rendering I may have to remove it and downgrade all the MyST upgrades I added into notebooks till next presentation of course in October 2025.

[agoose77]

It's a real shame that this is causing regressions for people. There are definitely some bugs that we can fix here. The notebook code is quite hard to architect around, so it might take some time. But I am going to dedicate some cycles to this.

[psychemedia]

@agoose77 thanks.. let me know if there's anything I can hlep look out for or test