Viewer embedding issues

The notebook cell is empty

Keep the returned viewer object alive, confirm the cell produced HTML output, and inspect the browser console for the first error. Then verify that the viewer URL shown by the Python object is reachable from the browser that renders the notebook.

The viewer frame cannot reach the local server

Remote notebooks, JupyterHub, and HTTPS notebook origins may need jupyter-server-proxy. The browser—not the Python kernel—must be able to reach the displayed URL.

The UI loads but the dataset does not

Inspect the first failing dataset request and its response body. A viewer-asset problem and a dataset-server problem are separate paths and should be diagnosed separately.

See Jupyter: show() and show_anndata() quickstart, Notebook / widget mode (advanced), and Troubleshooting (viewing).