Hello Genesis !

It can't be done by UNA settings, so you may try to remove it from preloader. It may be done via the execution of the following query in your UNA database (as usual - backup the table `sys_preloader` first):

DELETE FROM `sys_preloader` WHERE `content`='at.js/js/jquery.atwho.min.js' and `type`='js_system' LIMIT 1;