anchor.diff:  
     show: function() {
       this._setLink();
  -    this.$modeMenu.find('li').removeClass('selected');
  -    this.$modeMenu.find('.first').addClass('selected');
  +
  +    this.$modeMenu = $('.mode_menu');
  +    this.$modeMenu.find('.first')
  +      .addClass('selected')
  +      .siblings()
  +      .removeClass('selected')
   
       this.$el.fadeIn(250);
       this.$backdrop.show();
  
positive.code:     this.model.on('change:mode', this._toggleMode);
  
      this.$backdrop = $('.backdrop');
      this.$modeMenu = $('.mode_menu');
  
      var template = $('#share_dialog-template').html();
  
  
negative.code:         mode = $target.attr('data-embed');
  
      if (mode != this.model.get('mode')) {
        this.$modeMenu = $('.mode_menu');
  
        this.$modeMenu.find('li').removeClass('selected');
        $(e.currentTarget).parent().addClass('selected');
  
        this._setMode(mode);
      }
  