Hello, please, can you advise me how to fix the problem with content editing? I use Joomla 3.8.8, template Quark by Gavick and when I try to edit articles or some modules, it shows me this error message: "0 Class 'JSNConfigHelper' not found".
I guess it has something in common with the upgrading of the system, nevertheless, I had no proper backup to restore...
Thanks a lot for any advise! L