kiến thức Tổng hợp những addon chất cho Firefox / Chromium

(function () {
  var hook_eventNames = "contextmenu|select|selectstart|copy|cut|dragstart".split("|");
  var unhook_eventNames = "mousedown|mouseup|keydown|keyup".split("|");
  var eventNames = hook_eventNames.concat(unhook_eventNames);
  var storageName = getRandStr('qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM', parseInt(Math.random() * 12 + 8));
  var EventTarget_addEventListener = EventTarget.prototype.addEventListener;
  var document_addEventListener = document.addEventListener;
  var Event_preventDefault = Event.prototype.preventDefault;
  function addEventListener(type, func, useCapture) {
    var _addEventListener = this === document ? document_addEventListener : EventTarget_addEventListener;
    if (hook_eventNames.indexOf(type) >= 0) {
      _addEventListener.apply(this, [type, returnTrue, useCapture]);
    } else if (unhook_eventNames.indexOf(type) >= 0) {
      var funcsName = storageName + type + (useCapture ? 't' : 'f');
      if (this[funcsName] === undefined) {
        this[funcsName] = [];
        _addEventListener.apply(this, [type, useCapture ? unhook_t : unhook_f, useCapture]);
      }
      this[funcsName].push(func);
    } else {
      _addEventListener.apply(this, arguments);
    }
  }
  function clearLoop() {
    var elements = getElements();
    for (var i in elements) {
      for (var j in eventNames) {
        var name = 'on' + eventNames[j];
        if (elements[i][name] != null && elements[i][name] != onxxx) {
          if (unhook_eventNames.indexOf(eventNames[j]) >= 0) {
            elements[i][storageName + name] = elements[i][name];
            elements[i][name] = onxxx;
          } else {
            elements[i][name] = null;
          }
        }
      }
    }
  }
  function returnTrue(e) {
    return true;
  }
  function unhook_t(e) {
    return unhook(e, this, storageName + e.type + 't');
  }
  function unhook_f(e) {
    return unhook(e, this, storageName + e.type + 'f');
  }
  function unhook(e, self, funcsName) {
    var list = self[funcsName];
    for (var i in list) {
      list[i](e);
    }
    e.returnValue = true;
    return true;
  }
  function onxxx(e) {
    var name = storageName + 'on' + e.type;
    this[name](e);
    e.returnValue = true;
    return true;
  }
  function getRandStr(chs, len) {
    var str = '';
    while (len--) {
      str += chs[parseInt(Math.random() * chs.length)];
    }
    return str;
  }
  function getElements() {
    var elements = Array.prototype.slice.call(document.getElementsByTagName('*'));
    elements.push(document);
    return elements;
  }
  function addStyle(css) {
    var style = document.createElement('style');
    style.innerHTML = css;
    document.head.appendChild(style);
  }
  function init() {
    setInterval(clearLoop, 30 * 1000);
    setTimeout(clearLoop, 2500);
    window.addEventListener('load', clearLoop, true);
    clearLoop();
    EventTarget.prototype.addEventListener = addEventListener;
    document.addEventListener = addEventListener;
    Event.prototype.preventDefault = function () {
      if (eventNames.indexOf(this.type) < 0) {
        Event_preventDefault.apply(this, arguments);
      }
    };
    Event.prototype.__defineSetter__('returnValue', function () {
      if (this.returnValue != true && eventNames.indexOf(this.type) >= 0) {
        console.log(this);
        this.returnValue = true;
      }
    });
    console.debug('storageName:' + storageName);
    addStyle('html,*,:not(input):not(textarea):not(select), input[type="image"], input[type="file"], input[type="submit"], input[type="button"], input[type="reset"] {-webkit-user-select:text!important;-moz-user-select:text!important;user-select:text!important;}');
  }
  init();
})();