Troubleshooting#

Begin with an unchanged example on the exact host you intend to use. Record the source revision, operating system, browser or interpreter, and the full diagnostic when reporting a problem.

The preview is blank#

Opening the preview loads its interface; Run starts source execution. Check the status and expand diagnostics. The first execution needs network access for Pyodide resources. Confirm the full editor can run the same unchanged example. An unavailable GPU backend, worker startup failure and a Python exception require different fixes; do not infer success from the presence of an empty canvas.

A preview disappeared#

Documentation previews are released when the tab is hidden, another preview is opened, or Close is pressed. This avoids leaving several rendering contexts and Python workers active. Reopen and Run explicitly. For sustained editing, use the full editor instead of the documentation preview.

Import or native build fails#

Use the pinned Rust toolchain and supported CPython version. The development extension command needs the correct PYTHONPATH; an installed matching wheel should not. A wheel for another interpreter, ABI or platform will not become compatible by renaming it. Consult native Python details and the candidate guidance in the reference.

Text or equations differ from expectations#

Check the text constructor, font resources and whether you are using Typst or LaTeX. LaTeX preparation has its own host requirements. Start from the matching text example in the reference, not a different renderer's implicit asset or font behavior.

Seek, restart, or export is unavailable#

A live callback, unrecorded input, unfinished source continuation or unsupported replay domain may prevent the operation. This is not solved by forcing a seek button to appear. Check playback, the source's dependencies, and the export profile's documented admission requirements.

MP4 creation fails#

Confirm FFmpeg is installed with the needed encoder, the graphics driver supports capture, and the destination policy allows the output. Test a finite unchanged lesson first. Consult native export details for cancellation, limits and output handling.

How to report a useful issue#

Include a minimal source, exact revision or candidate filename, host details, expected result and complete diagnostic. A screenshot helps explain visual behavior; a short reproducible program helps distinguish semantics, host and renderer failures. Never include access tokens or private paths unnecessarily.