Git cannot be enabled (Nginx)

Operating system: Ubuntu
OS version: 20.04

I’ve tried to create an subserver and enabled Nginx and GIT:

I got the error:

Failed to modify server : Git cannot be enabled unless a website is
BTW: The error-message are really cutted off!

If I disable git, it works like expected.

Seems to be an old issue, but is still not fixed: Nginx + GIT