Notes

// ==UserScript==
// @name OGARio by szymy v3
// @namespace ogario.v3
// @version 3.4.2
// @description Unoffical Polish MOD
// @author szymy
// @match http://agar.io/*
// @updateURL http://cdn.ogario.ovh/v3/ogario.v3.user.js
// @run-at document-start
// @grant GM_xmlhttpRequest
// @connect agar.io
// ==/UserScript==

// © 2017 ogario.ovh

// Check location
if (location.host === "agar.io" && location.pathname === "/") {
location.href = "http://agar.io/ogario" + location.hash;
return;
}

// Dependencies
var ogarioCSS = '<link href="http://cdn.ogario.ovh/v3/ogario.v3.css?v=342" rel="stylesheet"></link>';
var ogarioSniffJS = '<script src="http://cdn.ogario.ovh/v3/ogario.v3.sniff.js?v=342"></script>';
var ogarioJS = '<script src="http://cdn.ogario.ovh/v3/ogario.v3.js?v=342" charset="utf-8"></script>';

var cpickerCSS = '<link href="http://cdn.ogario.ovh/static/css/bootstrap-colorpicker.min.css" rel="stylesheet"></link>';
var toastrCSS = '<link href="http://cdn.ogario.ovh/static/css/toastr.min.css" rel="stylesheet"></link>';
var switchCSS = '<link href="http://cdn.ogario.ovh/static/css/switchery.min.css" rel="stylesheet"></link>';
var rangeCSS = '<link href="http://cdn.ogario.ovh/static/css/rangeslider.css" rel="stylesheet"></link>';
var perfectCSS = '<link href="http://cdn.ogario.ovh/static/css/perfect-scrollbar.min.css" rel="stylesheet"></link>';

var cpickerJS = '<script src="http://cdn.ogario.ovh/static/js/bootstrap-colorpicker.min.js"></script>';
var toastrJS = '<script src="http://cdn.ogario.ovh/static/js/toastr.min.js"></script>';
var switchJS = '<script src="http://cdn.ogario.ovh/static/js/switchery.min.js"></script>';
var rangeJS = '<script src="http://cdn.ogario.ovh/static/js/rangeslider.min.js"></script>';
var perfectJS = '<script src="http://cdn.ogario.ovh/static/js/perfect-scrollbar.jquery.min.js"></script>';

// Inject OGARio
function inject(page) {
page = page.replace("</head>", cpickerCSS + toastrCSS + switchCSS + rangeCSS + perfectCSS + ogarioCSS + cpickerJS + toastrJS + switchJS + rangeJS + perfectJS + ogarioSniffJS + "</head>");
page = page.replace(/<script[^>]*>((?!<script)[sS])*?NREUM[sS]*?</script>/, "");
page = page.replace(/<script[^>]*>((?!<script)[sS])*?Outstream[sS]*?</script>/, "");
page = page.replace(/<script.*?src=".*?outstream.js.*?></script>/, "");
page = page.replace(/<script.*?src=".*?agario.core.js.*?></script>/, "");
page = page.replace("</body>", ogarioJS + "</body>");
return page;
}
window.stop();
document.documentElement.innerHTML = "";
GM_xmlhttpRequest({
method : "GET",
url : "http://agar.io/",
onload : function(e) {
var doc = inject(e.responseText);
document.open();
document.write(doc);
document.close();
}
});