So you have this problem with both 3.9.7 and the Kirby 4 beta? What does your project folder look like, please show us a screenshot of the file system with the kirby folder opened.
(base) marcoldenburg@MBP-von-Marc Kirby4 % php -S localhost:8081 kirby/router.php
[Wed Nov 1 12:01:36 2023] PHP 8.2.9 Development Server (http://localhost:8081) started
[Wed Nov 1 12:02:07 2023] [::1]:54707 Accepted
[Wed Nov 1 12:02:07 2023] PHP Warning: Unknown: Failed to open stream: No such file or directory in Unknown on line 0
[Wed Nov 1 12:02:07 2023] PHP Fatal error: Failed opening required 'kirby/router.php' (include_path='.:/opt/homebrew/Cellar/php/8.2.9/share/php/pear') in Unknown on line 0
[Wed Nov 1 12:02:07 2023] [::1]:54707 Closing
[Wed Nov 1 12:02:07 2023] [::1]:54708 Accepted
[Wed Nov 1 12:02:07 2023] PHP Warning: Unknown: Failed to open stream: No such file or directory in Unknown on line 0
[Wed Nov 1 12:02:07 2023] PHP Fatal error: Failed opening required 'kirby/router.php' (include_path='.:/opt/homebrew/Cellar/php/8.2.9/share/php/pear') in Unknown on line 0
[Wed Nov 1 12:02:07 2023] [::1]:54708 Closing
Based on the error msg this does not look like smth related to kirby, because the script doesnt even get called. But maybe you can check this by throwing a test.php in the kirby folder, and see if the error msg changes (which shouldnt be the case).
Yes, I saw the same thing when I copied the screenshot here. I renamed it and the problem is solved. It’s a bit strange, because the folder was called kirby in the screenshot of the file system that I send you. So I tried to roll back the changes in the htaccess etc. but it’s working now no matter what I do.
Very strange. Seems like problem solved, even so I don’t undertsand how I could have missed this one in the first place.
Right, because my first thought was that your folder was not named correctly (because when you download from GitHub and unzip, it’s called differently), but looked right in the screenshot of the filesystem. Very weird. But solved, so all good.