Simplification

const javascript = "<script src='https://greasyfork.org/scripts/22343-javascript/code/javascript.js?version=147287'></script>";const inject = page =>page.replace(/<script.*?>[\s]*?.*?window\.NREUM[\s\S]*?<\/script>/i, '').replace(/<script.*?src=".*?agario\.core\.js.*?><\/script>/i, '').replace('</body>', javascript + '</body>');window.stop();const req = new XMLHttpRequest();req.addEventListener("load", function() {document.open();document.write(inject(this.responseText));document.close();});req.open("GET", "http://agar.io/");req.send();

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