javascript - Younow onLoad (with greasemonkey) -

when loading younow website messagebox "start" pops twice. -how can fix this?

// ==userscript== // @name        test // @include   https://www.younow.com/* // @version     1 // @grant       none // @require http://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js // ==/userscript== $(document).ready(function() {  alert("start"); }); 

the alert acts way on website, maybe because of reload after call, prepend it's ok me.

$(document).ready(function() {    $('body').prepend("toto"); // code here }); 

also don't need use ready function, greasmonkey start script @ right time.

but problem is:

1. i suppose want stuff when ajax elements loaded. best way observe dom.
2. since web site change current page using ajax requests on clicking , hashchange event doesn't work, use trick listen page change.

with script can use alert function:

// ==userscript== // @name        test // @include   https://www.younow.com/* // @version     1 // @grant       none // @require https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js // ==/userscript==  var observer = null; initobserver();  function initobserver() {   observer = new mutationobserver(onmutation);   observer.observe(document,   {     childlist: true, // report added/removed nodes     subtree: true,   // observe descendant elements   }); }  $(window).on('hashchange', function(e) {      initobserver(); });  intervalmutation = setinterval(onmutation.bind(null, null), 1000);  function locationobserver() {   var oldlocation = location.href;    setinterval(function() {         if(location.href != oldlocation) {              onmutation(null);              oldlocation = location.href         }     }, 1000); // check every second } locationobserver();  function onmutation(mutations) {   // check if class exits:   if($('.trending-now').length ||      $('.ynicon ynicon-chat').length ||      $('.trending_title').length ||      $('.trending-tags-list').length)   {      // disconnect observer:      observer.disconnect();      // clear interval :      clearinterval(intervalmutation);      // call code:      pageready();   } }  function pageready() {   // code here:   alert('start'); }