I probably should, since the underlying renderer mentioned above is actually implemented using React (it takes as input JSON describing a notebook and renders i

I probably should, since the underlying renderer mentioned above is actually implemented using React (it takes as input JSON describing a notebook and renders it, entirely on the frontend). Also, in case it isn't clear, these days "Sage notebook" just means "Jupyter notebook with the SageMath kernel"... since "the Sage notebook" (=the SageMath project's predecessory to Jupyter, but written in 2007) is basically deprecated now in favor of the official Jupyter notebook project.