zendesk_helpcenter_live_reload_.js

// ==UserScript==
// @name         Zendesk Help Center - Live Update
// @namespace    http://pateo.co
// @version      0.1
// @description  Fetch local CSS file to render on Zendesk help center
// @author       Adam Gray
// @match        https://*.zendesk.com/hc/en-us*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    let lastSheet = generateStyleID();

    function generateStyleID() {
        return 'http://localhost:8000/style.css?r=' + Math.random() * 100000000000000000;
    }

    function appendStyleSheet(url) {
        $('body').append('<link rel="stylesheet" href="' + url + '">');
    }

    function removeStyleSheet(url) {
      $('link[rel=stylesheet][href~="' + url + '"]').remove();
    }

    function reload() {
        let thisSheet = generateStyleID();
        appendStyleSheet(thisSheet);
        setTimeout(() => {
          removeStyleSheet(lastSheet);
          lastSheet = thisSheet;
        }, 100);
    }

    appendStyleSheet(lastSheet);
    setInterval(reload, 2000);
})();