diff --git a/src/backends/widget.js b/src/backends/widget.js
index cb4d35423919b3c5f54975096b6cec349b8a1a24..6c6cfa23a85859d008f918073d9f8c4ba4850f26 100644
--- a/src/backends/widget.js
+++ b/src/backends/widget.js
@@ -18,6 +18,8 @@ import WidgetApi from 'matrix-widget-api';
 
 class WidgetBackend extends BaseBackend {
   constructor(widgetId, userId) {
+    super();
+
     this.userId = userId;
 
     this.api = new WidgetApi(widgetId);