check if relatedTarget is undefined for fallback

facebook · Aug 13, 2020 · ccdf9c2 · ccdf9c2
1 parent 0d1fb7b
commit ccdf9c2
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/packages/react-dom/src/events/SyntheticEvent.js b/packages/react-dom/src/events/SyntheticEvent.js
@@ -170,7 +170,7 @@ export const MouseEventInterface = {
   button: 0,
   buttons: 0,
   relatedTarget: function(event) {
-    if (!event.relatedTarget && event.fromElement)
+    if (event.relatedTarget === undefined)
       return event.fromElement === event.srcElement
         ? event.toElement
         : event.fromElement;