Tweets +1 Chrome Extension for Google +1 Button and twitter.com

addgoogleplusonecode.js

var plusOneScript = document.createElement('script');
plusOneScript.setAttribute("src", "https://apis.google.com/js/plusone.js");
plusOneScript.textContent = '{"parsetags": "explicit"}';
plusOneScript.addEventListener("load", function() {
    var script = document.createElement("script");
    script.textContent = "var addPlusOne = function(){gapi.plusone.go();setTimeout(addPlusOne, 1000);};setTimeout(addPlusOne, 1000);";
    document.body.appendChild(script);
}, false);
document.body.appendChild(plusOneScript);

findTweets.js

var findTweets = function(event) {
    var node = event.target;
    if (node.webkitMatchesSelector && node.webkitMatchesSelector('div[data-item-type=tweet]')) {
        addPlusOne(node);
    } else if (node.querySelectorAll) {
        var tweets = node.querySelectorAll('div[data-item-type=tweet]');
        for (var i = 0; i < tweets.length; i++) {
            addPlusOne(tweets[i]);
        }
    }
}

listener.js

document.body.addEventListener("DOMNodeInserted", findTweets, false);

manifest.json

{
  "name" : "Tweets +1",
  "version" : "1.0",
  "description" : "Adds a +1 button to tweets on twitter.com",
  "content_scripts" : [
    {
      "matches" : [
        "http://twitter.com/*",
        "https://twitter.com/*"
      ],
      "js" : ["contentscript.js"],
      "run_at" : "document_idle",
      "all_frames" : false
    }
  ],
  "icons" : {
    "128" : "tweets+1.png"
  }
}