/config is empty

[root9191]

Hello,
what is the /config Directory for? After executing Compose File in /data and /mysql are files but not in /config.
I tried the Installation first in my VM and there the config.php was created. When i switched to my Raspi the Folders where created but there was no file in it. Afterwards in the Nextcloud Installation i had to fill in all Database Details again.
On my Raspi i used the CasaOS Installation from TMC Store - but i guess the Compose File is nearly the same except the Directories, which was the only thing i changed here.