Support “Add to Codex Thread” for selected code in Jupyter Notebook cells

What variant of Codex are you using?

IDE Extension

What feature would you like to see?

I would like the Codex VS Code extension to support adding selected code
from Jupyter Notebook (.ipynb) cells directly to the current Codex thread.

Environment:

• macOS
• VS Code
• Codex extension version: 26.810.41047
• Microsoft Python and Jupyter extensions installed

Steps to reproduce:

1. Open an .ipynb file in VS Code.
2. Select code inside a Jupyter code cell.
3. Right-click and choose “Add to Codex Thread”.
4. Nothing is added to the Codex composer, and no error is displayed.

Expected behavior:
The selected code should appear as context in the current Codex composer,
including the notebook filename and preferably the cell identity.

Actual behavior:
The command has no visible effect.

Important comparison:
The same selected Jupyter cell code can be added successfully to VS Code’s
built-in Chat, so the notebook selection itself is working.

This feature is important for learning, data analysis, and notebook-based
Python workflows. Copying and pasting manually loses file and cell context.

Additional information

_No response_