mylloon.fr/static/js/libs/katex.js

window.addEventListener("load", () => {
  const macros = {};
  for (const item of new Map(
    Object.entries({
      N: "mathbb{N}",
      R: "mathbb{R}",
      Z: "mathbb{Z}",
      O: "Theta",
      ra: "rightarrow",
      la: "leftarrow",
      RA: "Rightarrow",
      LA: "Leftarrow",
      u: "mu",
    })
  )[Symbol.iterator]()) {
    macros[`\\${item[0]}`] = `\\${item[1]}`;
  }

  const attribute = "data-math-style";
  for (let element of document.querySelectorAll(`span[${attribute}]`)) {
    katex.render(element.textContent, element, {
      throwOnError: false,
      displayMode: element.getAttribute(attribute) === "display",
      macros,
      output: "mathml",
    });
  }
});