     settingEmail: null
     settingProps: {}
     selectedConversationId: null
-    # lastUsed: []
 
     currentView: null
 

        return

      button = bar.append new GMailUI.ButtonBarPopupButton popup, '', (__msg 'extName')

      errorSection = popup.append new GMailUI.ErrorSection __msg 'errorNoActionSpecified' # __msg 'errorNoTimeSpecified'

      isValid()

    @SCHEDULE_SUFFIX: '/schedule'
    @SETUP_URL_SUFFIX: '/setup'

    @CLS:         'mailfred'
    #@CLS_NAV:     M.CLS + '-nav'
    @CLS_THREAD:   M.CLS + '-thread'
    @CLS_POPUP:    M.CLS + '-popup'
    @CLS_MENU:     M.CLS + '-menu'
    @CLS_PICKER:   M.CLS + '-picker'
    @CLS_LOADER:   M.CLS + '-loader'

    @ID_PREFIX:    M.CLS + '-id-'

    @TYPE_THREAD:  'thread'
    @TYPE_NAV:     'nav'

    @STORE:
      BOX_SETTING:  'settings'
      DEBUG:        'debug'
      EMAIL:        'email'
      LAST_VERSION: 'lastVersion'

    @GM_SEL:
      ARCHIVE_BUTTON:                 '.T-I.J-J5-Ji.lR.T-I-ax7.T-I-Js-IF.ar7:visible'
      THREAD_BUTTON_BAR:              '.iH > div'
      INSERT_AFTER:                   '.G-Ni.J-J5-Ji:visible:nth-child(3)'
      PREVIEW_PANE_ENABLED:           '.apF .apJ'
      PREVIEW_PANE_THREAD_BUTTON_BAR:  "[gh='mtb'] > div > div"

    # URL
