diff --git a/h5p-metadata.class.php b/h5p-metadata.class.php
index 8462fa4..73223b1 100644
--- a/h5p-metadata.class.php
+++ b/h5p-metadata.class.php
@@ -90,7 +90,7 @@ abstract class H5PMetadata {
       $exists = array_key_exists($key, $metadata);
 
       // Don't include missing fields
-      if (!$include_missing && !exists) {
+      if (!$include_missing && !$exists) {
         continue;
       }
 
diff --git a/h5p.classes.php b/h5p.classes.php
index b0099bc..d1c05fa 100644
--- a/h5p.classes.php
+++ b/h5p.classes.php
@@ -1864,7 +1864,7 @@ class H5PCore {
     'js/h5p-utils.js',
   );
 
-  public static $defaultContentWhitelist = 'json png jpg jpeg gif bmp tif tiff svg eot ttf woff woff2 otf webm mp4 ogg mp3 wav txt pdf rtf doc docx xls xlsx ppt pptx odt ods odp xml csv diff patch swf md textile vtt webvtt';
+  public static $defaultContentWhitelist = 'json png jpg jpeg gif bmp tif tiff svg eot ttf woff woff2 otf webm mp4 ogg mp3 m4a wav txt pdf rtf doc docx xls xlsx ppt pptx odt ods odp xml csv diff patch swf md textile vtt webvtt';
   public static $defaultLibraryWhitelistExtras = 'js css';
 
   public $librariesJsonData, $contentJsonData, $mainJsonData, $h5pF, $fs, $h5pD, $disableFileCheck;
@@ -3402,8 +3402,14 @@ class H5PContentValidator {
    */
   public function validateMetadata($metadata) {
     $semantics = $this->getMetadataSemantics();
-
     $group = (object)$metadata;
+
+    // Stop complaining about "invalid selected option in select" for
+    // old content without license chosen.
+    if (!isset($group->license)) {
+      $group->license = 'U';
+    }
+
     $this->validateGroup($group, (object) array(
       'type' => 'group',
       'fields' => $semantics,
diff --git a/js/jquery.js b/js/jquery.js
index 90a3b83..a05d556 100644
--- a/js/jquery.js
+++ b/js/jquery.js
@@ -13,3 +13,8 @@ var H5P = window.H5P = window.H5P || {};
  * @member
  */
 H5P.jQuery = jQuery.noConflict(true);
+H5P.jQuery.ajaxPrefilter(function (s) {
+  if (s.crossDomain) {
+    s.contents.script = false;
+  }
+});