diff --git a/web/js/app.js b/web/js/app.js
index 209dbf07df..808b198bf8 100644
--- a/web/js/app.js
+++ b/web/js/app.js
@@ -263,3 +263,7 @@ App.propTypes = {
   parameters: PropTypes.object,
   setScreenInfoAction: PropTypes.func,
 };
+
+App.defaultProps = {
+  numberOutagesUnseen: 0
+};