code: function () {
      var spectatorCameraEl = this.spectatorCameraEl;
  
      if (!spectatorCameraEl) {
        this.el.addEventListener('spectatorcameracreated',
                                 bind(this.activateSpectatorCamera, this));
        return;
      }
  
      if (!spectatorCameraEl.hasLoaded) {
        spectatorCameraEl.addEventListener('loaded', bind(this.activateSpectatorCamera, this));
        return;
      }
  
      log('Activating spectator camera');
      spectatorCameraEl.setAttribute('camera', 'active', true);
      this.cameraEl.getObject3D('replayerMesh').visible = true;
    }
docs: Activate spectator camera, show replayer mesh.