I have a notebook that contains embedded Vega-Lite visualizations and an embedded PNG file that shows up as a cell attachment. When I run jupyter nbconvert notebook.ipynb --to notebook, no notebook_files/ subdirectory gets created to hold the attachment. I’ve tried to explicitly enable the ExtractOutput preprocessor with --ExtractOutputPreprocessor.enabled=True, but still no subdirectory gets created. The same goes if I specify --to markdown, which I had expected to create a subdirectory for attached images.
Under what circumstances is the notebook_files/ subdirectory created and populated with files? Curious if I’m missing something, or if something is broken. Thanks!