Issue #3257600 by tstoeckler, rpayanm: SettingsTrayBlockFormTest needlessly overrides getTestThemes

    }

  }

  /**

   * {@inheritdoc}

   */

  protected function getTestThemes() {

    // Remove 'seven' theme. Setting Tray "Edit Mode" will not work with 'seven'

    // because it removes all contextual links the off-canvas dialog should.

    return array_filter(parent::getTestThemes(), function ($theme) {

      return $theme !== 'seven';

    });

  }

}