Facebook message count

Show facebook message count on https://www.facebook.com/messages
目前為 2016-11-23 提交的版本，檢視最新版本。
安裝腳本 ?
換行
// ==UserScript==
// @name         Facebook message count
// @namespace    http://tampermonkey.net/
// @version      0.2
// @description  Show facebook message count on https://www.facebook.com/messages
// @author       Tomáš Falešník
// @match        https://www.facebook.com/messages/*
// @grant        none
// @require      http://code.jquery.com/jquery-latest.js
// ==/UserScript==
 
(function() {
    'use strict';
    var observeDOM = (function(){
        var MutationObserver = window.MutationObserver || window.WebKitMutationObserver,
            eventListenerSupported = window.addEventListener;
 
        return function(obj, callback){
            if( MutationObserver ){
                // define a new observer
                var obs = new MutationObserver(function(mutations, observer){
                    if( mutations[0].addedNodes.length || mutations[0].removedNodes.length )
                        callback();
                });
                // have the observer observe foo for changes in children
                obs.observe( obj, { childList:true, subtree:true });
            }
            else if( eventListenerSupported ){
                obj.addEventListener('DOMNodeInserted', callback, false);
                obj.addEventListener('DOMNodeRemoved', callback, false);
            }
        }
    })();
 
    observeDOM($("body")[0], function() {
        var messageHeader = $("#webMessengerHeaderName");
        if (messageHeader.length) {
            var messageCount = $("._7hx > span").html();
            if (!$("#messageCount").length) {
                $('<h2 class="_r7" style="max-width: 286px; font-size: 13px;"> (<span id="messageCount"></span> +- messages)</h2>').insertAfter(messageHeader);
            }
            $("#messageCount").html(messageCount);
        }
    });
})();