jupyterlab-export-markdown-extension

jupyterlab_export_markdown_extension

[!TIP] This extension is part of the stellars_jupyterlab_extensions metapackage. Install all Stellars extensions at once: pip install stellars_jupyterlab_extensions

Export markdown files to PDF, DOCX, and HTML directly from JupyterLab. No external dependencies required - just pip install and go.

Features

• PDF Export - Full Unicode and emoji support via reportlab
• DOCX Export - Microsoft Word documents with smart image sizing (fit-to-page for large images)
• HTML Export - Standalone files with embedded images
• LaTeX Math - Native OMML equations in DOCX (editable in Word), KaTeX in HTML, PNG images in PDF
• GitHub Alerts - Colored alert boxes for [!NOTE], [!TIP], [!IMPORTANT], [!WARNING], [!CAUTION] with left border and background shading in DOCX/PDF
• Mermaid Diagrams - Rendered server-side to PNG via Playwright Chromium at the configured SVG export width
• Embedded Images - Local images automatically converted to base64
• Syntax Highlighting - Code blocks with Pygments-powered coloring
• Wide Tables - Tables wider than the page wrap within a fitted column layout instead of running past the margin, in PDF, DOCX and HTML
• Merged Cells - colspan and rowspan on raw HTML table cells merge in DOCX and PDF
• Task Lists - - [x] / - [ ] render as checkbox glyphs in HTML, DOCX and PDF
• Lists and Callouts - two-space nested lists render as lists, every ordered list restarts at 1, and a bordered <div> draws as a box - a uniform border as a frame in its own line style, an accented one with its bar - in DOCX and PDF
• Inline HTML - <span style="color:...">, font-weight, font-style, text-decoration, <mark>, <del>, <ins>, <kbd>, <font color>, align= and <div> render as written in DOCX and PDF
• Symbol Glyphs - ★ ☆ ✓ ✗ ☐ ☒, arrows and box drawing name a font of their own in DOCX, so they look the same in every reader's Word
• Export Spinner - Modal dialog shows progress during export operations
• File Menu Integration - "Export Markdown As" submenu appears when markdown is active
• Command Palette - All export commands available via Ctrl+Shift+C
• Command Line - jupyterlab-export-markdown-extension convert exports a file to PDF, DOCX and HTML without JupyterLab running
• Settings - Configure export font size, SVG export width, math export width, themes, and alert label visibility via Settings Editor
• Pure Python - No pandoc, no LaTeX, no system dependencies

Requirements

• JupyterLab >= 4.0.0
• Python >= 3.10

For PDF export, install required system libraries and emoji font:

# Ubuntu/Debian
sudo apt-get install libcairo2 libpango-1.0-0 libpangoft2-1.0-0 fonts-noto-color-emoji

Mermaid diagrams are rendered client-side using JupyterLab's built-in Mermaid support - no additional installation required. An export driven through the REST endpoints instead of the UI has no browser to render them, so the server renders those diagrams itself with a bundled copy of Mermaid, in the same Playwright Chromium the SVG rasterizer uses - no network access involved.

A diagram that cannot be rendered never fails the export: its source is kept and the response carries an X-Export-Warnings header describing what happened, as a JSON array of {code, count, diagrams, message}. code is one of chromium-unavailable, bundle-missing, syntax-error, layout-unsupported, render-timeout, skipped, budget-exhausted, rasterize-failed or render-failed; count is how many diagrams the warning covers, diagrams a bounded prefix of their zero-based positions in the document, and message the remedy in full - a caller needs nothing beyond the header. An image that is not embedded - its file does not exist or is outside the server root, or its download failed - is reported under the code image-not-embedded, with images, the first 3 of its paths as written, in place of diagrams; HTML keeps such an image's path, DOCX and PDF show a text placeholder. The header is absent when every diagram rendered and every image was embedded, and is listed in Access-Control-Expose-Headers so a cross-origin caller can read it.

Install

pip install jupyterlab_export_markdown_extension

That's it. No really, that's actually it. We spent considerable effort making sure you don't have to install pandoc, LaTeX, or sacrifice a goat to get this working.

Usage

1. Open a markdown file in JupyterLab
2. Use File -> Export Markdown As submenu, or
3. Open command palette (Ctrl+Shift+C) and search "Export Markdown"

Command Line

The package installs jupyterlab-export-markdown-extension, which converts a file without JupyterLab running. convert starts a private Jupyter server inside the command and calls the same export endpoints as the menu, so the result matches a UI export made with default settings; the one difference is that Mermaid diagrams render in the server's bundled Mermaid instead of the browser's.

jupyterlab-export-markdown-extension convert report.md --to pdf docx html
jupyterlab-export-markdown-extension check     # test that Chromium launches
jupyterlab-export-markdown-extension install   # download Chromium and its system libraries

• Each document is written beside the source, or to -o PATH when there is one format; an existing file is overwritten
• Images are read only from inside --root (default: the current directory) - pass a folder that holds the file and every image it links to, such as the repository root; an image that is not embedded is named in a warning on stderr
• Your own Jupyter configuration is not read, so a contents root or log level set there does not change the export
• --theme, --font-size and --alert-labels set what the settings below set in the UI
• jupyterlab-export-markdown-extension --help lists the commands, the exit codes and examples; <command> --help documents that command's flags and output

An agent skill for AI coding assistants is in .agents/skills/jupyterlab-export-markdown-extension. pip install also copies it to <sys.prefix>/share/jupyter/agents/skills/jupyterlab-export-markdown-extension, a folder no agent reads. Link it from there, with the Python that runs JupyterLab:

mkdir -p ~/.agents/skills && ln -s "$(python -c 'import sys; print(sys.prefix)')/share/jupyter/agents/skills/jupyterlab-export-markdown-extension" ~/.agents/skills/jupyterlab-export-markdown-extension

From a clone, link it into Claude Code:

ln -s "$PWD/.agents/skills/jupyterlab-export-markdown-extension" ~/.claude/skills/jupyterlab-export-markdown-extension

Export Formats

Settings

Configure the extension via Settings -> Settings Editor -> Markdown Export Extension:

• Export Font Size - Base body text size for all three formats: small (10pt), medium (12pt, default), large (13pt). Every other size - headings, tables, code, captions - is a fixed proportion of it, so the whole document scales together
• SVG Export Pixel Width - Target pixel width for SVG images and Mermaid diagrams rasterized server-side in DOCX/PDF (default: 1920, range: 400-4096). Height follows the source aspect ratio
• Math Export Pixel Width (PDF only) - Target pixel width for math expression images in PDF export (default: 800, range: 200-3000). DOCX uses native OMML equations and HTML uses KaTeX, neither affected by this setting
• Show Alert Labels - Display alert type labels (NOTE, TIP, etc.) in exported documents (default: off)

Uninstall

pip uninstall jupyterlab_export_markdown_extension

Contributing

If you would like to contribute to this extension, please refer to the Contributing Guide.

License

BSD 3-Clause License