diff --git a/dom/html/HTMLImageElement.h b/dom/html/HTMLImageElement.h
index 6fba0bf15f13..7d856a1c2d5b 100644
--- a/dom/html/HTMLImageElement.h
+++ b/dom/html/HTMLImageElement.h
@@ -199,7 +199,7 @@ public:
   }
 
   mozilla::net::ReferrerPolicy
-  GetImageReferrerPolicy()
+  GetImageReferrerPolicy() override
   {
     return GetReferrerPolicy();
   }