diff --git a/app/assets/javascripts/discourse/models/store.js.es6 b/app/assets/javascripts/discourse/models/store.js.es6
index 4e6e68dab6..96a96f502f 100644
--- a/app/assets/javascripts/discourse/models/store.js.es6
+++ b/app/assets/javascripts/discourse/models/store.js.es6
@@ -312,7 +312,7 @@ export default Ember.Object.extend({
             obj[subType] = hydrated;
             delete obj[k];
           } else {
-            obj[subType] = null;
+            Ember.set(obj, subType, null);
           }
         }
       }