XAMPP is an open-source bundle of Apache + MariaDB + PHP + Perl and most popular PHP development environment. It bundles different versions of PHP and allows for local development of Apache/PHP server setups.

After installing a PHP 8 version of XAMPP - and renaming the XAMPP folders - I got the following error message:

Apparently, XAMPP does not like being renamed.

Workaround: Rename the version you want to work with to XAMPP, then the manager-osx will start.