matplotlib / matplotlib/ipympl
Javascript error sometimes
- Dominant language
- Jupyter Notebook
- Stars
- 1.7k
- Forks
- 234
- PR merge metrics
- No merged PRs in 30d
Description
Javascript error sometimes
```
at WidgetManager.loadClass (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2457634)
at WidgetManager.loadClass (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2841448)
at WidgetManager.loadModelClass (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2454419)
at WidgetManager._make_model (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2452380)
at WidgetManager.new_model (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2450099)
at WidgetManager.handle_comm_open (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2448870)
at https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-renderers-1.3.0/out/node_modules/%40vscode/jupyter-ipywidgets8/dist/ipywidgets.js:2:2840461
at t._handleCommOpen (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-2025.7.0-linux-x64/dist/webviews/webview-side/ipywidgetsKernel/ipywidgetsKernel.js:3:119000)
at async t._handleMessage (https://file+.vscode-resource.vscode-cdn.net/home/firestar/.vscode/extensions/ms-toolsai.jupyter-2025.7.0-linux-x64/dist/webviews/webview-side/ipywidgetsKernel/ipywidgetsKernel.js:3:120875)
```
restart kernel won't fix
Contributor guide
Research direction
Start by reproducing the failure in the VS Code Jupyter environment described by the stack trace, using the ipympl widget. Inspect the WidgetManager.loadClass and handle_comm_open stack entries in ipywidgets.js and ipywidgetsKernel.js, then compare the installed Jupyter, renderer, and widget versions. Done means identifying the trigger and confirming that the intermittent JavaScript error no longer occurs.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, jupyter, jupyter-notebook, vscode
- Domain
- frontend
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100