HSBC UK Individual - Human friendly account names

gistfile1.js

// ==UserScript==
// @name         HSBC Personal - Human friendly account names
// @namespace    http://github.com/skrobul
// @version      0.2
// @description  This scripts adds user-friendly names for your HSBC accounts. It can help with managing multiple accounts.
// @author       skrobul <skrobul@skrobul.com>
// @match        https://www.services.online-banking.hsbc.co.uk/*
// @grant        none
// ==/UserScript==

(function() {
    var accountNames = {
        '40-02-26 12345678': 'Main current',
        '40-02-26 91234576': 'Education',
        '40-02-26 12731405': 'Holiday fund',
    };

   function updateNames() {
       var accounts = document.getElementsByClassName('itemName');
       for (var i = 0; i < accounts.length ; i++) {
           var el = accounts[i];
           var origName = el.innerText.trim();
           if(accountNames[origName] !== undefined) {
               el.innerText = el.innerText + " " + accountNames[origName];
           }
       }
   };

   // wait for the Dojo app to be fully initialized. adjust this if needed. defaults to 5 seconds
   setTimeout(function() { updateNames() }, 5000);

 })();

Hi This doesn't work for me. Can you give steps to use it? I got your link from the chap who wrote the Business Banking script (https://gist.github.com/chrisroos/8862244).
Thanks!