https://armada.buzz/standalone.js

1/*
2 * Standalone (home-screen PWA) launch marker. Marks the launch on <html>
3 * before first paint so CSS can scroll-lock the shell (see index.css).
4 *
5 * External rather than inline because index.html carries a strict
6 * Content-Security-Policy whose `script-src` permits no inline script. Loaded
7 * from <head> in document order, like theme.js.
8 */
9(function () {
10  "use strict";
11
12  if (
13    window.matchMedia("(display-mode: standalone), (display-mode: fullscreen)").matches ||
14    window.navigator.standalone === true
15  ) {
16    document.documentElement.classList.add("standalone");
17  }
18})();