Fix mediatag preview

www/common/inner/common-mediatag.js

@@ -284,11 +284,13 @@ define([
                     'data-crypto-key': key
                 });
                 $inner.append(tag);
+                setTimeout(function () {
                     MediaTag(tag).on('error', function () {
                         locked = false;
                         $spinner.hide();
                         UI.log(Messages.error);
                     });
+                });
             }
 
             var observer = new MutationObserver(function(mutations) {