Save and restore widget state in jupyter notebooks

[bcm0]

Is your feature request related to a problem? Please describe.

I'm always frustrated when the widget state is lost

Describe the solution you'd like

It would be cool to be able to save and restore widget state in the jupyter notebook metadata automatically somehow.

Describe alternatives you've considered

Panel lets you sync the widgets state with the url (https://panel.holoviz.org/how_to/state/url.html#sync-and-unsync) and Param lets you save and restore state from JSON (https://param.holoviz.org/user_guide/Serialization_and_Persistence.html),

[jbednar]

I'd love to see this as well!