I ran into this too. I was able to work around it by switching the Jupyter extension to the pre-release version (which was a suggestion in a different question that I can't find anymore).
Answer from Alex Trzyna on Stack OverflowGitHub
github.com › microsoft › vscode-jupyter › issues › 14459
Jupyter for vscode continues to be slow (for large notebooks with mardown cells & large outputs) · Issue #14459 · microsoft/vscode-jupyter
October 7, 2023 - 2) Jupyter for vscode sucks at inline documentation, the equivalent of shift+tab in vscode jupyter. I am aware of the existence of the trigger parameter hints and show hover settings in the keyboard shortcuts.
Author loftusa
GitHub
github.com › microsoft › vscode-jupyter › issues
Issues · microsoft/vscode-jupyter
microsoft / vscode-jupyter Public · Notifications · You must be signed in to change notification settings · Fork 377 · Star 1.5k · September Endgame · #17019 · Yoyokrazy opened · on Oct 1, 2025 · 3 · Unable to run notebook cells with spaces in path · #17042 · dakenblack opened · on Oct 10, 2025 · 14 · Search Issues ·
Author microsoft
Jupyter Notebook extension Visual Studio Code stuck "connecting to kernel" - Stack Overflow
It seems to be an issue with the version 7.0.0 of the ipykernel python package. The jupyter notebook extension in vscode as well as the jupyter notebook in the browser get stuck in kernel connecting state when a cell is executed. More on stackoverflow.com
Jupyter Interactive Window stuck in pending due to _VSCODE_getVariable request
Applies To Notebooks (.ipynb files) Interactive Window and/or Cell Scripts (.py files with #%% markers) What happened? The Interactive Window gets stuck in "pending" when the jupyter vari... More on github.com
4
January 21, 2026VSCode slow and crashes - Python and Jupyter Notebooks
Type: Performance Issue Hi, When working with large Python Notebook files and restart the kernel, it takes way too long to do so and most often than not it crashes. When opening VSCode again, all t... More on github.com
14
March 8, 2024Execute notebook cell freezes
Applies To Notebooks (.ipynb files) Interactive Window and/or Cell Scripts (.py files with #%% markers) What happened? In the last week or so the jupter extension frequently hangs when trying the e... More on github.com
2
October 28, 2025Videos
Top answer 1 of 2
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I ran into this too. I was able to work around it by switching the Jupyter extension to the pre-release version (which was a suggestion in a different question that I can't find anymore).
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solved downgrading to previous version (November 2022) then updating to latest version again. Running same Python and Jupyter version. Good luck
Top answer 1 of 3
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It's not the Visual Studio Code update. I've been experimenting on a virtual machine, after my students started complaining this week that their Jupyter Notebooks stopped working...
I've tried downgrading Visual Studio Code, but that didn't solve the problem, so I started looking somewhere else.
As far as I know right now, the problem lies in the Jupyter-extension.
I have first disabled the Auto Update for the Jupyter-extension.
Next, I have downgraded the extension to version 2025.7.0, and it works again.
For good measure, I've then tried to update to version 2025.8.0: it also works.
But, when using version 2025.9.0: it breaks!
So what I would recommend:
In the Extensions-tab, disable Auto Update for the Jupyter extension.
Then use the Install Specific Version-menu to install version 2025.8.0.
After further testing:
The alternative is to Switch to Pre-Release Version, at least version 2025.10.2025101001. That also works.
UPDATE 2025-10-16:
Jupyter extension version 2025.9.1 has been released. This fixes the issue as well.
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It seems to be an issue with the version 7.0.0 of the ipykernel python package. The jupyter notebook extension in vscode as well as the jupyter notebook in the browser get stuck in kernel connecting state when a cell is executed. On installing ipykernel==6.30.1, which is the version before 7.0.0, I don't face this issue in vscode or jupyter notebook in browser.
I have created an issue for the same: https://github.com/ipython/ipykernel/issues/1445
Hence I think we have to use ipykernel==6.30.1 until the issue is fixed. You can install it by running
pip install ipykernel==6.30.1
P.S.: ipykernel 7.0.1 has been released and it fixes this issue.
Visual Studio Code
code.visualstudio.com › docs › datascience › jupyter-notebooks
Jupyter Notebooks in VS Code
November 3, 2021 - To work with Python in Jupyter Notebooks, you must activate an Anaconda environment in VS Code, or another Python environment in which you've installed the Jupyter package.
GitHub
github.com › microsoft › vscode-jupyter › issues › 17271
Jupyter Interactive Window stuck in pending due to _VSCODE_getVariable request · Issue #17271 · microsoft/vscode-jupyter
January 21, 2026 - Applies To Notebooks (.ipynb files) Interactive Window and/or Cell Scripts (.py files with #%% markers) What happened? The Interactive Window gets stuck in "pending" when the jupyter variables view is unable to retrieve variable values. ...
Author flori-ko
GitHub
github.com › microsoft › vscode-jupyter › discussions › 13031
VScode notebook never stops executing but issues no errors · microsoft/vscode-jupyter · Discussion #13031
When executing a cell the cell just keeps running and never stops and never issues an error. VSCODE juputer notebooks used to work so I rolled back the install a bit but still get the same problem. It seems to be mostly on imports.
Author microsoft
GitHub
github.com › microsoft › vscode-jupyter › issues › 15351
VSCode slow and crashes - Python and Jupyter Notebooks · Issue #15351 · microsoft/vscode-jupyter
March 8, 2024 - freeze-slow-crash-leakVS Code crashing, performance, freeze and memory leak issuesVS Code crashing, performance, freeze and memory leak issuesinfo-neededIssue requires more information from posterIssue requires more information from posternotebook-executionKernels issues (start/restart/switch/execution, install ipykernel)Kernels issues (start/restart/switch/execution, install ipykernel)perfPerformance issuesPerformance issues ... When working with large Python Notebook files and restart the kernel, it takes way too long to do so and most often than not it crashes. When opening VSCode again, all the workspaces/folders are closed and have to open them again. Also regarding Python + Jupyter, doing some quick benchmarking between VSCode and JupyterLab (or Notebook), VSCode feels like a snail.
Author ale-dg
GitHub
github.com › microsoft › vscode-jupyter › issues › 17124
Execute notebook cell freezes · Issue #17124 · microsoft/vscode-jupyter
October 28, 2025 - Applies To Notebooks (.ipynb files) Interactive Window and/or Cell Scripts (.py files with #%% markers) What happened? In the last week or so the jupter extension frequently hangs when trying the execute cells. It shows as executing, but...
Author trondbn
GitHub
github.com › microsoft › vscode-jupyter › issues › 7352
Jupyter notebook stuck loading, not showing content, in VSCode · Issue #7352 · microsoft/vscode-jupyter
August 31, 2021 - microsoft / vscode-jupyter Public · Notifications · You must be signed in to change notification settings · Fork 375 · Star 1.5k · New issueCopy link · New issueCopy link · Closed · Closed · Jupyter notebook stuck loading, not showing content, in VSCode#7352 ·
Author Dervis-vL
GitHub
github.com › microsoft › vscode › issues › 173509
Jupyter is not running cells · Issue #12750 · microsoft/vscode-jupyter
February 5, 2023 - I am using jupyter with conda. It was running proparly, after updating to Jan release jupyter stopped working with all of my environment. To reproduce the error, install the latest versions of jupyter on conda enviroment with lateset version of VSCode and required extentions to run jupyter.
Author alsediqi
GitHub
github.com › microsoft › vscode-jupyter › issues › 17089
Jupyter loads forever on running a cell, even after the 2025.9.1 patch on Windows 11 Home · Issue #17089 · microsoft/vscode-jupyter
October 14, 2025 - Unlike previous instances wherein the issue got temporarily resolved by downgrading to 2025.8.0, this time the issue does not get resolved even upon downgrading. I tried a complete reinstall. As part of the uninstall process, I wiped clean every VSCode file in my laptop. I removed the AppData, the Local and cache folder files pertaining to VSCode or Jupyter.
Author sushantnair
GitHub
github.com › microsoft › vscode-jupyter › issues › 15101
I am installing the jupyter extension on my VsCode and its failing with a Vscode version error. · Issue #15101 · microsoft/vscode-jupyter
January 31, 2024 - I am installing the jupyter extension on my VsCode and its failing with a Vscode version error.#15101 ... bugIssue identified by VS Code Team member as probable bugIssue identified by VS Code Team member as probable bug ... Unable to install extension 'ms-toolsai.jupyter' as it is not compatible with VS Code '1.85.2'. [NOTE: Self-contained, minimal reproducing code samples are extremely helpful and will expedite addressing your issue]
Author 4qmbjamil
GitHub
github.com › microsoft › vscode-jupyter › issues › 17081
Kernel not connecting to Python or Jupyter after latest VS Code update · Issue #17081 · microsoft/vscode-jupyter
October 12, 2025 - Type: Bug After updating to the latest version of Visual Studio Code (October 2025 update), Jupyter notebooks no longer connect to the Python kernel. Both Python and Jupyter work perfectly fine when launched from the terminal, but inside...
Author AbdelrahmanAli098
GitHub
github.com › microsoft › vscode-jupyter › issues › 11031
VS Code crashes when running a cell that produces a lot of output · Issue #11031 · microsoft/vscode-jupyter
August 3, 2022 - I am trying to print model summary in tensorflow and I think the model is large and it's crashing my notebook. The model is ResNet101. The whole computer comes to a halt, memory usage goes up to 99% and VS Code crashes. I have 16 GB of r...
Author ydmykr
GitHub
github.com › microsoft › vscode-jupyter › issues › 17231
ipywidgets does not render inside of VSCode jupyter notebook · Issue #17231 · microsoft/vscode-jupyter
December 27, 2025 - I have tried uninstall and reinstalling package versions that other sources suggested would work better together (e.g., using python3.10 instead of 3.13, downgrading the notebook package, etc.), updating all of the VSCode extensions, creating a clean venv environment to start from scratch, running code for a different widget, and restarting vscode entirely.
Author Aeslyn
GitHub
github.com › continuedev › continue › issues › 1463
Jupyter Notebooks in VSCode become unresponsive because the kernel gets disposed erroneously · Issue #1463 · continuedev/continue
June 10, 2024 - $onExtensionActivationError @ workbench.desktop.main.js:sourcemap:1985 workbench.desktop.main.js:sourcemap:651 INFO [perf] Render performance baseline is 19ms workbench.desktop.main.js:sourcemap:651 ERR [Extension Host] ex workbench.desktop.main.js:sourcemap:148 [Extension Host] ex p @ workbench.desktop.main.js:sourcemap:148 workbench.desktop.main.js:sourcemap:651 ERR [Extension Host] Error: timeout at Timeout.p (/home/jeffliu/.vscode-server/extensions/ms-toolsai.jupyter-2024.2.0-linux-x64/dist/extension.node.js:55:1754) at listOnTimeout (node:internal/timers:569:17) at process.processTimers (
Author jeffliu-LL
GitHub
github.com › microsoft › vscode-jupyter › issues › 17167
Jupyter notebook cells get stuck in selection mode after highlighting text in VS Code · Issue #17167 · microsoft/vscode-jupyter
November 26, 2025 - The cell should remain editable and responsive after highlighting text. When selecting or highlighting text inside a Jupyter notebook cell, the cell frequently becomes “stuck” in selection mode.
Author dannasharonpinto-dev
GitHub
github.com › microsoft › vscode-jupyter › issues › 16834
VSCode Copilot Agent causes .ipynb cell content to disappear after edits — rendering failure in Notebook editor · Issue #16834 · microsoft/vscode-jupyter
July 25, 2025 - When using GitHub Copilot Agent to modify code in .ipynb (Jupyter Notebook) files, the edited cell becomes completely blank — no code is shown, and the cell cannot be interacted with. This occurs regardless of the model used (GPT-4, GPT-4o, Claude 3.5/4). The issue seems to be related to VSCode’s Notebook rendering breaking after Agent edits.
Author Broderick-23
Reddit
reddit.com › r/vscode › jupyter notebook in vs code stuck. malfunctioning
r/vscode on Reddit: Jupyter notebook in Vs code STUCK. Malfunctioning
March 10, 2026 - Jupyter Extension Activation Failed Can't Run Any Notebook Cells. HELPP ... Using VS Code to automate my workflows is insane!(ly) awesome! ... Intellisense AutoComplete Not Working anymore. Tried restarting VSCode, and it starts working for a moment before just quitting.