Saving Notebooks when multiple editors for same notebook are opened

[DonJayamanne]

Widgets in Jupyter Notebooks have state in them.
It is possible to save a Jupyter notebook with the state information in the ipynb file.
This way, when the ipynb file is opened, the widget state is available and it can be rendered (even without a real kernel).

Saving widget an nb with widget state is optional, and we as extension authors can some how prompt/determine whether this additional information needs to be saved or not.

However, if a user has multiple editors for the same notebook opened, then its possible the widget state on both are completely different.

• We have other issues when opening a notebook document multiple times SaveAs functionality in Notebook API #97274

Possible solution

• Allow extension the ability to control whether a notebook document can be opened multiple times or not (doesn't feels like a solution, more of a bandaid)
  • Then again, the custom editor supports this as well, I guess this is a valid solution.

@rebornix /cc

[DonJayamanne]

Closing as this has been discussed with @rebornix