1 files changed, 6 insertions, 1 deletions
diff --git a/_nav/html/index.php b/_nav/html/index.php
index 31ba1d514..7297f84ec 100644
--- a/_nav/html/index.php
+++ b/_nav/html/index.php
@@ -9,6 +9,11 @@ $url  = isset($_GET['u']) ? trim($_GET['u']) : null;
 
 /** html[lang] of the doc. */
 $lang = isset($_GET['l']) ? trim($_GET['l']) : null;
+if ($lang == 'undefined' ||
+    $lang == '') {
+
+    $lang = 'en';
+}
 
 /** body[class] of the doc. */
 $body = isset($_GET['b']) ? trim($_GET['b']) : null;
@@ -25,4 +30,4 @@ header('Access-Control-Allow-Origin: *');
 header('Access-Control-Allow-Methods: GET');
 header('Content-Type: text/html;charset=utf-8');
 header(sprintf('Expires: %s', gmdate('r', strtotime('+1 day'))));
-echo _mgnav_html($wrap, $lang);
-\ No newline at end of file
+echo _mgnav_html($wrap, $lang);