Fresh installation of Fedora IoT 39 under a raspberry Pi 3 (arm-image-installer --target=rpi3).

Apparently any symlink created or removed under /etc/systemd/system (like "systemctl disable ModemManager" or "systemctl set-default graphical.target" - I haven't checked under other /etc folders) is not kept for the next reboot.
Creating a file (like a new service) works. I'm pretty sure that worked well under Fedora IoT 38.

My current workaround in fact is to make a service who force the right target and usind predefined services configuration to enable my new services.

Of course I installed xfce before to run “systemctl set-default graphical.target”.

GT