Also hide feedback text when clearing items

src/plugins/muc-views/modals/muc-list.js

@@ -113,6 +113,7 @@ export default class MUCListModal extends BaseModal {
     onDomainChange () {
         this.getElementsByClassName('form-control')[0].value = this.model.get('muc_domain');
         this.items = [];
+        this.model.save('feedback_text', '');
         api.settings.get('auto_list_rooms') && this.updateRoomsList();
     }