I am trying to add a plugin to the cell toolbar that retrieves all the code and output above a certain cell and sends it to a backend once clicked. My output might contain visualizations, and I want to capture that information as well. I can handle the backend part of this but I am at a loss regarding how to get all the cell content and cell output. To achieve this, what should I list for the requires
attribute and how do I go from there? Thank you!!