Extension activation failed, run the 'Developer: Toggle Developer Tools' command for more information.

[Charan208]

Type: Bug

in Extension activation failed, run the 'Developer: Toggle Developer Tools' command for more information.
workbench.desktop.main.js:3105 Extension activation failed, run the 'Developer: Toggle Developer Tools' command for more information.
onDidChangeNotification @ workbench.desktop.main.js:3105
workbench.desktop.main.js:759 Activating extension 'ms-python.python' failed: Attempt to insert a duplicate controller with ID "python-tests".
$onExtensionActivationError @ workbench.desktop.main.js:759

Extension version: 2024.22.1
VSCodium version: VSCodium 1.96.2 (29b115fb6fb418b80e93102cb177e06803e7b907, 2024-12-21T00:46:06.606Z)
OS version: Windows_NT x64 10.0.19045
Modes: Restricted

System Info

Item	Value
CPUs	Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz (4 x 3094)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: unavailable_off raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: unavailable_off webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	3.87GB (0.81GB free)
Process Argv	C:\Users\Ravindar\Desktop\import speech_recognition as sr.py
Screen Reader	no
VM	33%

[karthiknadig]

@Charan208 This looks like a case of bad install. Try uninstalling the extension, and removing all instances of it from the extension directory and try again.

[HeyErfan]

@Charan208, install the latest version first. Once it's installed, go to the extensions tab, Right-Click on the extension, and you'll see an option saying “Install Specific Version.” After clicking on the “Install Specific Version” button, select a relatively older version (for example, 2025.3.0). Now wait for it to install, and the issue should be resolved.

[tanjuntao]

@Charan208, install the latest version first. Once it's installed, go to the extensions tab, Right-Click on the extension, and you'll see an option saying “Install Specific Version.” After clicking on the “Install Specific Version” button, select a relatively older version (for example, 2025.3.0). Now wait for it to install, and the issue should be resolved.

This works for me. Thank you.

[andreadmf]

@Erfan-0 Thank you very much bro, I have been trying to fix it for two whole days but haven't found it, then I was just reading your comment and I tried it and it worked. Thank you very much, it really really helps.

[hjs60789-creator]

@Charan208, install the latest version first. Once it's installed, go to the extensions tab, Right-Click on the extension, and you'll see an option saying “Install Specific Version.” After clicking on the “Install Specific Version” button, select a relatively older version (for example, 2025.3.0). Now wait for it to install, and the issue should be resolved.

your My GOD THANK YOU SO MUCH Mr.EXPERT

[CQUPT-CZL]

resolved

Thinks my bro, your solution is good work!

[kwdiwt]

@Charan208, install the latest version first. Once it's installed, go to the extensions tab, Right-Click on the extension, and you'll see an option saying “Install Specific Version.” After clicking on the “Install Specific Version” button, select a relatively older version (for example, 2025.3.0). Now wait for it to install, and the issue should be resolved.

Thinks my bro

[mrBlackHat777]

Download the VSIX for Linux x64: Download Jupyter v2025.7.0 (linux-x64)

rename it to jupyter.vsix.

Run the following command in your WSL terminal:

antigravity --install-extension jupyter.vsix

Windows users: Change the targetPlatform in the URL to win32-x64 to get the correct build for your OS.

[DrNickBailey]

I've just had this same sudden fail of the python extensions causing the Testing sidebar window to disappear. In my case it happened when trying to debug why VSCode was not finding my python tests (with my ever helpful 'Norbot' assistant). Norbot doesn't admit to having changed anything.

I tried uninstalled all my extensions and reinstalled various Python versions to no avail but eventually Norbot "found the root cause" explained as follows:

"python.useEnvironmentsExtension": true in your global user settings was forcing the Python extension to bind to the env extension's API, which in version 1.36.0 doesn't expose onDidChangeEnvironment, crashing activation.

That sounds familiar to the OP so I hope this helps the next human/Norbot.

EDIT: I should note that my original testing issue was not fully fixed - I think there's some fundamental confusion in VSCode when using a "workspace" which contains a number of git repos as "fodlers added to workspace".