Greasy Fork is available in English.

HTML Animation Frame Request Limiter

Limits HTML animation frame request. Practically limits FPS of JavaScript controlled animation such as in canvas. Designed to lower CPU usage.

// ==UserScript==
// @name        HTML Animation Frame Request Limiter
// @namespace   https://greasyfork.org/en/users/85671-jcunews
// @version     1.0.1
// @license     AGPL v3
// @author      jcunews
// @description Limits HTML animation frame request. Practically limits FPS of JavaScript controlled animation such as in canvas. Designed to lower CPU usage.
// @match       *://*/*
// @include     *:*
// @grant       GM_registerMenuCommand
// @grant       unsafeWindow
// @run-at      document-start
// ==/UserScript==

(() => {
  var fps = 0, tfps, pt, raf = unsafeWindow.requestAnimationFrame;
  function nraf(f) {
    if (fps && !f.f_ujs) {
      var nf = function(t) {
        if ((t - pt) >= tfps) {
          pt = t;
          return nf.f_ujs.apply(this, arguments)
        } else setTimeout(() => raf(nf), tfps - (t - pt))
      };
      nf.f_ujs = f;
      f = nf;
    } else if (!fps && f.f_ujs) f = f.f_ujs;
    return raf.apply(this, arguments)
  }
  GM_registerMenuCommand("Set FPS", a => {
    a = fps;
    while (true) {
      a = prompt(`Context: [${window.top === window ? "Host" : "Frame"}]\n${location.href}\n\nFPS limiter is currently ${fps ? "set to: " + fps : "disabled"}.\nEnter new FPS rate (e.g.: 20), or zero to disable limiter.`, a);
      if (a === null) return;
      if (!isNaN(a = parseFloat(a.trim())) && (a >= 0)) {
        if (fps = a) {
          tfps = 1000 / fps;
          pt = 0;
          unsafeWindow.requestAnimationFrame = nraf
        } else unsafeWindow.requestAnimationFrame = raf;
        return
      }
    }
  })
})()