Ticket #24449: 24449.5.diff

wp-includes/js/media-views.js

@@ -462 +462 @@
                 },
 
                 canEmbed: function( attachment ) {
-                        var type = attachment.get('type');
-                        if ( type !== 'audio' && type !== 'video' )
-                                return false;
+                        // If uploading, we know the filename but not the mime type.
+                        if ( ! attachment.get('uploading') ) {
+                                var type = attachment.get('type');
+                                if ( type !== 'audio' && type !== 'video' )
+                                        return false;
+                        }
 
                         return _.contains( media.view.settings.embedExts, attachment.get('filename').split('.').pop() );
                 },