twitter_timeline_update

var target_tweet = document.getElementsByClassName("stream-container")[0];
var observer = new MutationObserver(function(mutations) {
    for (var i = 0; mutations[i]; i++)
        document.getElementsByClassName("new-tweets-bar")[0].click();
});
var config = { attributes: true, childList: true, characterData: true }
observer.observe(target_tweet, config);