Jupyter Notebook rendering takes forever eternity asgard time

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1

Jupyter notebook file doesnt render after the recent update to 3.0.

It takes forever time to load, actually not load just taking forever time = doesnt show up any cells.

.py works fine, same issue doesnt happen on vscode

Version: 3.0.12 (system setup)
VSCode Version: 1.105.1
Commit: a80ff7dfcaa45d7750f6e30be457261379c29b00
Date: 2026-04-04T00:13:18.452Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.19044

2

Hi there!

We detected that this may be a bug report, so we’ve moved your post to the Bug Reports category.

To help us investigate and fix this faster, could you edit your original post to include the details from the template below?

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Where does the bug appear (feature/product)?

  • Cursor IDE
  • Cursor CLI
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Expected Behavior
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Operating System

  • Windows 10/11
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Version Information

  • For Cursor IDE: Menu → About Cursor → Copy
  • For Cursor CLI: Run agent about in your terminal
IDE:
Version: 2.xx.x
VSCode Version: 1.105.1
Commit: ......

CLI:
CLI Version 2026.01.17-d239e66

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Does this stop you from using Cursor?

  • Yes - Cursor is unusable
  • Sometimes - I can sometimes use Cursor
  • No - Cursor works, but with this issue

The more details you provide, the easier it is for us to reproduce and fix the issue. Thanks!

4

I encountered the same problem. It takes lot of time to open any Jupyter Notebook file while it works fine with .py scripts. The IDE just loading but not showing any cells.
However if you close all the cursor windows and wait for a bit, it will work sometimes.

It’s not unusable, just very annoying.

5

Even after closing all my cursor windows, its stil lthe same for me even for a newly created jupyter notebook :frowning:

6

Hey, thanks for the report. This looks like a regression after 3.0.

For now, let’s try to narrow it down:

  1. Open a terminal and run cursor --disable-extensions, then check if notebooks render without extensions. If they do, the issue is caused by one of them, and we can look for the specific one.

  2. Open Process Explorer Ctrl+Shift+P, then Developer: Open Process Explorer while the notebook is stuck loading, and send a screenshot. I’m mainly interested in what’s using CPU and RAM.

  3. Which Jupyter extensions are installed. Just the default ms-toolsai.jupyter, or anything extra?

@Ferris_Jiang, are you on the same 3.0.12 version. And which OS?

Let me know what you find. That’ll help us figure this out faster.

8

for whatever reason png upload is not possible. giving u the text

Process Name | CPU (%) | Memory (MB) | PID

cursor main | 0 | 191 | 37432
extensionHost [2] | 0 | 188 | 2056
window [2] (factor_builder_v9_1.ipynb - esgQuant - Cursor) | 1 | 467 | 5952
utility-network-service | 0 | 67 | 6264
extensionHost [2] | 0 | 190 | 15188
shared-process | 0 | 154 | 18124
gpu-process | 0 | 171 | 20232
window [3] (Process Explorer) | 0 | 128 | 27956
ptyHost | 0 | 128 | 28832
extensionHost [2] | 0 | 192 | 28980
crashpad-handler | 0 | 52 | 35440
fileWatcher [2] | 0 | 127 | 36680
extensionHost [2] | 0 | 187 | 36720

9

takes still a bit of time compared to VSCode but cursor 2.6 works

10

I have the same issue in Cursor 3.0.13: I can’t open a .ipynb file. I already tried disabling the extensions, but I still have the same issue. I have the Jupyter extension ms-toolsai.jupyter, I’m working on Windows 11. I’m gonna uninstall the cursor and reinstall it, that’s the only way it works.

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image1593×757 18.5 KB

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image1276×758 12.8 KB

I open Developer Tools and see that the extension ms-toolsai.jupyter has a conflict. I’m gonna try uninstalling the cursor and changing the extension.

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image893×833 76.7 KB

11

Thanks for your reply.

I’m on the same 3.0.12 version of cursor and working with Windows 11. For my hardwares they are almost idle, with plently room and capacity so I don’t think it’s their problem.

I did nothing after my feedback. However it works fine by now for my notebook extension.

Strange but it automatically solved?

12

same thing here… it is so unstable using jupyter notebook on Cursor.