This repository is a collection of web demos and examples for MathJax version 4, the JavaScript math rendering library. It demonstrates various ways to integrate MathJax into web pages, including standard TeX/MathML input with CHTML/SVG output, equation numbering and referencing, interactive reveal/toggle steps, speech generation, and compatibility with MathJax v2 configurations. The repo also contains a substantial custom font extension named 'mathjax-newcm' (New Computer Modern) that provides extensive glyph metrics and SVG path data for mathematical typesetting, with a specific focus on braille output (the 'euro-braille' subdirectory). This font data is split into dynamic chunks loaded on demand by MathJax. The codebase is primarily illustrative—each demo is a self-contained HTML page with accompanying JavaScript. The custom component and TeX extension examples show how to build tailored MathJax bundles using internal APIs. The configuration converter is a standalone utility that parses legacy MathJax v2 configuration objects and generates equivalent v4 configuration. While the demos are functional and well-organized, the font data files are minified/generated artifacts that are difficult to maintain manually, and several parts rely on MathJax internal APIs that may change across versions. The euro-braille and euro-braille-old directories contain near-duplicate font data with version drift, indicating a maintenance challenge. Overall, this repo serves as a practical reference for MathJax v4 integration patterns and custom font development, but it is not a production library itself. The most reusable components are the custom component assembly pattern, the TeX extension template, and the configuration converter utility.