diff --git a/src/core/HNode.ts b/src/core/HNode.ts
index 2b7910a..4c5a7a1 100644
--- a/src/core/HNode.ts
+++ b/src/core/HNode.ts
@@ -79,7 +79,7 @@ export const toNodeArr = function toNodes(
 
         if (_isArray(src) && src.length) {
 
-            return src.flat(_Infinity).map(s => toNodeArr(s, context, ownerNode, owner)).flat();
+            return src.flat(_Infinity).flatMap(s => toNodeArr(s, context, ownerNode, owner));
 
         } else if (isHNode(src)) {
 
diff --git a/test/test.html b/test/test.html
index 1900f3a..3dbdc67 100644
--- a/test/test.html
+++ b/test/test.html
@@ -19,8 +19,9 @@
 
 <body>
     <div id="portal"></div>
-    <script src="../dist/hyper-ui.core.umd.js"></script>
-    <script src="./test.js"></script>
+    <script type="text/javascript" crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/hpolyfill" defer="defer"></script>
+    <script src="../dist/hyper-ui.core.umd.js" defer="defer"></script>
+    <script src="./test.js" defer="defer"></script>
 </body>
 
 </html>
\ No newline at end of file
diff --git a/test/tsconfig.json b/test/tsconfig.json
index fee6536..598b805 100644
--- a/test/tsconfig.json
+++ b/test/tsconfig.json
@@ -1,8 +1,13 @@
 {
   "compilerOptions": {
-    "target": "esnext",
+    "target": "es5",
     "module": "none",
     "jsx": "react",
+    "lib": [
+      "dom",
+      "es2015",
+      "es2016"
+    ],
     "jsxFactory": "HUI",
     "outFile": "./test.js",
     "rootDir": "./src",
