A softer light theme for MDN based on the colours of the FT/FD

MDN-FD-light-theme.js

// ==UserScript==
// @name        MDN FD light theme
// @namespace   Violentmonkey Scripts
// @match       https://developer.mozilla.org/*
// @grant       none
// @version     1.0
// @author      SJongeJongeJonge
// @description 24/08/2024, 19:40:19
// ==/UserScript==

const css = `
.light {
  --background-primary: #f1ded2;
  --background-secondary: #e5d1c6;
  --border-primary: #cdbeb4;
  --code-background-inline: #F5E8E0;
  --code-background-block: #F5E8E0;
}

/* In case the white backgrounds of the code samples are to bright, you can dim the backgrounds with this:
iframe.nobutton, iframe.sample-code-frame, iframe[src*="https://jsfiddle.net"], iframe[src*="https://mdn.github.io"], iframe[src*="https://test262.report"], iframe[src*="https://www.youtube-nocookie.com"] {
  background: #F2EAE5;
}
*/
`;

const head = document.getElementsByTagName("head")[0];
let elem = document.createElement("style");
elem.textContent = css;
head.appendChild(elem);