Troubleshooting and supported behavior

Symptom	Action
Import cannot be found	Install using %pip in the active notebook, then restart the kernel.
Notebook HTML is unstyled	Trust your own notebook or execute its display cells yourself. Some hosted platforms strip CSS.
Old fonts or colors after upgrading	Restart the kernel, recreate the deck and execute the display cells again. Existing saved outputs retain the old HTML.
Duplicate slide numbers or exported sections	Recreate the deck or use deck.clear(), then run the display cells in order.
SQL / Java / C++ has no syntax colors	Install the [highlight] extra. Plain-text fallback remains supported.
Display area is narrow	Collapse Jupyter side panels or use standalone HTML. Components adapt to their output width.
Answer not shown in a printed handout	Expand the answer disclosure before printing. Closed answers remain closed in print.
docs says documentation is missing	In a source checkout, run python tools/build_docs.py. Installed releases include the built site.

Support scope

The core renderer runs without IPython or Pygments. Notebook display uses IPython, and optional surrounding-cell styling targets JupyterLab. Modern CSS features such as container queries are used. Colab and other hosted notebook services have not been validated, and no automatic PDF conversion is included.

Displayed code is never executed by the renderer. Export includes only the components accumulated in that deck; independent notebook cells and their results are outside its export.

Keep your lecture reproducible

Record the package version used for a course. Before distributing a revised handout, restart the kernel and run display cells from the identity cell onward. Export the final HTML after all intended components have been added.