ClockworkSquirrel / [NCS] Change Name

// ==UserScript==
// @name         [NCS] Change Name
// @description  Change your name on the New College VLE site.
// @version      1.0.3
// @run-at       document-start
// @match        http*://vle.newcollege.ac.uk/*
// @require      https://code.jquery.com/jquery-3.1.1.min.js
// @require      https://pastebin.com/raw/nEq3ZVCM
// @grant        GM_setValue
// @grant        GM_getValue
// @grant        GM_registerMenuCommand
// @grant        GM_addValueChangeListener
// @grant        GM_addStyle
// ==/UserScript==

var myName = GM_getValue("setUserName", null);

(function() {
    'use strict';

	function updateName(){
		if (myName === null) return;
		var searchTerm;
		
		$("span.usertext").each(function(){
			searchTerm = $(this).text().trim();
			$(this).parent().html($(this).parent().html().replace(new RegExp(searchTerm, "g"), myName));
		});
		
		$("title").text($("title").text().replace(new RegExp(searchTerm, "g"), myName));
	}
	
    $("span.usertext").waitUntilExists(updateName);
	$(document).ready(updateName);
	
	GM_addStyle("header#header div.header-top{position:fixed;z-index:9999999;width:100%;margin-top:-60px} header#header div.header-main{margin-top:60px}");
	
	GM_registerMenuCommand("Change Name", function(){
		GM_setValue("setUserName", prompt("Name"));
	});
	
	GM_addValueChangeListener("setUserName", function(name, oldValue, newValue){
		myName = newValue;
		updateName();
	});
})();