after installing a slider extension I can't get it to display properly in the frontend. There are just the pictures and text without any formatting or functionality. It is correctly configured, but loading the css/js files fails (Error 403 in browser console). I checked the directory. The files are there and permissions are 755/644. I also noticed that in my htaccess file everything in the root folder is redirected to error 403. Does this have anything to do with it?
System: Magento 2.1, Plesk 12, Ubuntu 14.04 Website: http://speedswim.de/
EDIT: Following Error in error_log: Symbolic link not allowed or link target not accessible