Load new tweets automatically.

com.twitter.user.js

(function() {

// ==UserScript==
// @name Load new tweets automatically.
// @namespace http://matthewlmcclure.com
// @match https://twitter.com/*
// ==/UserScript==

    var updating = true;
    var event = document.createEvent('MouseEvents');
    event.initEvent('click', true, true);

    window.setInterval(function () {
        var updateButton = document.getElementsByClassName('js-timeline-title')[0] ||
            document.getElementsByClassName('js-stream-title')[0];
        updateButton.onclick = function() {
            updating = ! updating;
        }

        if (updating) {
            updateButton.innerText = 'Stop updating';
            var elements = document.getElementsByClassName('new-tweets-bar');
            var newTweetsBar;
            
            if (elements.length === 1 && window.pageYOffset < 100) {
                newTweetsBar = elements[0];
                newTweetsBar.dispatchEvent(event);
            }
        } else {
            updateButton.innerText = 'Update automatically';
        }

   }, 1000);

})();