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src/app/room/room.component.html

@@ -9,7 +9,7 @@
   <mat-list-item>Closed: {{room.closed}}</mat-list-item>
 
   <button mat-button routerLink="/room/{{room.id}}/create-comment">
-    Create comment
+    Create comment <!-- Only for participant -->
   </button>
 </mat-list>