diff --git a/runtime/src/launcher/js/launcher.js b/runtime/src/launcher/js/launcher.js
index 9b53b760d6a..ac0567daa2d 100644
--- a/runtime/src/launcher/js/launcher.js
+++ b/runtime/src/launcher/js/launcher.js
@@ -19,7 +19,7 @@ let heap;
 let global_arguments;
 
 function isBrowser() {
-    return typeof window !== 'undefined';
+    return typeof self !== 'undefined';
 }
 
 let runtime;