I tried to google this but got nowhere. Does anyone know what is wrong?
Also, I got the latest version Omeka running on a virtual machine, locally but I was only able to do so by using older versions of PHP (7.7.24) and MySQL (5.7.34).
Are there any issues with newer versions of PHP and/or MySQL?
The latest version of Classic should run fine on the latest PHP and MySQL versions.
The issue you’re seeing where you’re seeing the code rather than the actual application: that’s not a version issue really, but some other problem with your server setup: seeing the code means your server is not set up to execute PHP correctly.