opencart 1.5.6.2 image not showing filemanager problem

the image manager does not show the images, reverting the changed system/helper/utf8.php file to the 1.5.6.1 version seems to solve the problem for now.

system/helper/utf8.php with https://github.com/opencart/opencart/blob/b84978b5ca6683d4c62951256ef25f68a685ce92/upload/system/helper/utf8.php