View difference between Paste ID: zcEyFPdw and tShv5zX7

 // ==UserScript==
 // @name       Detect new comments on Hashtable's blog
 // @namespace  http://h16free.pltplp.net/
 // @version    0.2
 // @description Detect new comments since last visit on h16free.com blog. This version supports comments on multiple pages
 // @match      http://h16free.com/*
 // @copyright  2013, Etienne Bernard
 // ==/UserScript==
 
 // a function that loads jQuery and calls a callback function when jQuery has finished loading
 function addJQuery(callback) {
     var script = document.createElement("script");
     script.setAttribute("src", "//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js");
     script.addEventListener('load', function() {
         var script = document.createElement("script");
         script.textContent = "window.jQ=jQuery.noConflict(true);(" + callback.toString() + ")();";
         document.body.appendChild(script);
     }, false);
     document.body.appendChild(script);
 }
 
 // the guts of this userscript
 function main() {
 
     var cookies;
     var readCookie = function(name,c,C,i){
         if(cookies){ return cookies[name]; }
         c = document.cookie.split('; ');
         cookies = {};
         for(i=c.length-1; i>=0; i--){
             C = c[i].split('=');
             cookies[C[0]] = C[1];
         }
         return cookies[name];
     };
 
     var articleId = jQ('article.entry-plain').attr('id');
     if (articleId) {
 	    articleId = articleId.substr(5);
         // Get comments' page
         var hr = jQ('article.comment-block:first header a').attr('href');
         var commentPage = parseInt(hr.replace(/#.*/, '').replace(/^.*comment-page-/, ''), 10);
 	    var cookieName = 'lastVisits';
 	    // Check if we have a cookie for this article
 	    var cookie = readCookie('lastVisits');
         var lastVisits = {};
 	    if (cookie !== undefined) {
             lastVisits = JSON.parse(cookie);
         }
         // Get last visit time
         var key = 'p' + articleId + '-' + commentPage;
         var lastViewed = lastVisits[key];
         if (lastViewed !== undefined) {
             // Mark as new
 	        jQ('article.comment-block > header > a > time').each(function() {
 	            var t = new Date(jQ(this).attr('datetime'));
-	            t = t.getTime() - 7200000; // Fix timezone
+	            t = t.getTime() - 3600000; // Fix timezone
 	            if (t > lastViewed) {
 	                jQ(this).parents('article').parent('li').css('outline', '2px dotted red');
 	            }
 	        });
         }
         lastVisits[key] = new Date().getTime();
         // Set cookie for next time
 	    document.cookie = cookieName + '=' + JSON.stringify(lastVisits) + ';path=/;expires=Tue, 31 Dec 2019 23:00:00 GMT';
     }
 }
 
 // load jQuery and execute the main function
 addJQuery(main);