diff --git a/wp-content/themes/twentytwelve/functions.php b/wp-content/themes/twentytwelve/functions.php
index f4f347e483..e399343ee0 100644
--- a/wp-content/themes/twentytwelve/functions.php
+++ b/wp-content/themes/twentytwelve/functions.php
@@ -98,7 +98,7 @@ function twentytwelve_scripts_styles() {
 	/*
 	 * Adds JavaScript for handling the navigation menu hide-and-show behavior.
 	 */
-	wp_enqueue_script( 'twentytwelve-navigation', get_template_directory_uri() . '/js/navigation.js', array(), '20120824', true );
+	wp_enqueue_script( 'twentytwelve-navigation', get_template_directory_uri() . '/js/navigation.js', array(), '20120920', true );
 
 	/*
 	 * Loads our special font CSS file.
diff --git a/wp-content/themes/twentytwelve/js/navigation.js b/wp-content/themes/twentytwelve/js/navigation.js
index e544e292cd..1260f61bae 100644
--- a/wp-content/themes/twentytwelve/js/navigation.js
+++ b/wp-content/themes/twentytwelve/js/navigation.js
@@ -7,9 +7,15 @@
 	var button = document.getElementById( 'site-navigation' ).getElementsByTagName( 'h3' )[0],
 	    menu   = document.getElementById( 'site-navigation' ).getElementsByTagName( 'ul' )[0];
 
-	if ( undefined == button || undefined == menu )
+	if ( undefined === button )
 		return false;
 
+	// Hide button if menu is missing or empty.
+	if ( undefined === menu || ! menu.childNodes.length ) {
+		button.style.display = 'none';
+		return false;
+	}
+
 	button.onclick = function() {
 		if ( -1 == menu.className.indexOf( 'nav-menu' ) )
 			menu.className = 'nav-menu';
@@ -22,8 +28,4 @@
 			menu.className += ' toggled-on';
 		}
 	};
-
-	// Hide menu toggle button if menu is empty.
-	if ( ! menu.childNodes.length )
-		button.style.display = 'none';
 } )();
\ No newline at end of file