docs: function addonsManager_waitforOpened(aSpec) {
      var spec = aSpec || { };
      var timeout = (spec.timeout == undefined) ? TIMEOUT : spec.timeout;
  
      // TODO: restore after 1.5.1 has landed
      // var self = this;
      //
      // mozmill.utils.waitFor(function() {
      //   return self.isOpen;
      // }, timeout, 100, "Add-ons Manager has been opened");
      
      mozmill.utils.waitForEval("subject.isOpen", timeout, 100, this);
  
      // The first tab found will be the selected one
      var tab = this.getTabs()[0];
      tab.controller.waitForPageLoad();
  
      return tab;
    }