diff --git a/web/gui2/src/main/webapp/app/fw/util/prefs.service.ts b/web/gui2/src/main/webapp/app/fw/util/prefs.service.ts
index 3cef9b6..f696125 100644
--- a/web/gui2/src/main/webapp/app/fw/util/prefs.service.ts
+++ b/web/gui2/src/main/webapp/app/fw/util/prefs.service.ts
@@ -21,7 +21,9 @@
 /**
  * ONOS GUI -- Util -- User Preference Service
  */
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class PrefsService {
 
     constructor(