@janvankuijk@sorgentegianluca I really appreciate you guys reporting this. It is very strange to me, as I tried to replicate this error on two of my test servers, but no error comes up. I even setup a clean installation of Joomla 4 to test it, and no error shows up for me. I know something is wrong because of your reports, and I am eager to sort it out.
I need you guys to temporarily turn on “Debug System” under the “System” tab in Global Configuration. Then try to go the the Dashboard for Easy Folder Listing Pro again. This should show the error stack trace and provide some more detail.
I was also wondering what version of PHP you are using? I know Jan is on PHP 8. I am in the process of setting up another test server with PHP 8 to see if it is because of that, as my existing servers use PHP 7.4.
@janvankuijk@sorgentegianluca Ok, guys. I solved the issue. It has to do with namespace case sensitivity and auto-loading. Normally, PHP namespaces are case-insensitive (see https://www.php.net/manual/en/language.namespaces.rationale.php). It seems as though, for some unknown reason, the auto-loading of classes in Joomla 4 for some PHP installations require exact letter case of the namespaced class and the file location. None of my test servers have this issue. So, I can’t diagnose it on my end. I figured it out based on examining the differences between the servers and the errors, etc.
Anyways, I got Jan’s extension up and running. I am going to patch up Version 4.0 to 4.0.1 with this minor fix, and get everyone else up and running. Thanks for the cooperation.