Expand shortened URLs on Twitter (userscript for Firefox and Google Chrome)

ExpandShortURLs.user.js

// ==UserScript==
// @name        ExpandShortURLs
// @namespace   maripo.org
// @description Expand shortened URL on Twitter
// @include     https://twitter.com/*
// @version     1
// ==/UserScript==

(function()
    {
        setInterval (function()
        {
            var links = document.getElementsByTagName('A');
            for(i=0; i<links.length; i++)
            {
                link = links[i];
                attr = link.getAttribute('data-ultimate-url');
                if (attr)
                {
                    link.innerHTML = decodeURIComponent(attr);
                    link.href = attr;
                }
            }
        },
        1000);
    }
)();