Added async to script-tag

index.html

@@ -115,7 +115,7 @@
 	<script defer type="text/javascript" src="assets/js/multiselect.js"></script> -->
 
 	<!-- Production -->
-	<script defer type="text/javascript" src="assets/build/main.js"></script>
+	<script async type="text/javascript" src="assets/build/main.js"></script>
 
 	</body>
 </html>