Problem
On upgrade to Fedora 43, nftables.service may be disabled if it was previously enabled.
Cause
We believe this happens because the service file was split into a separate package (nftables-services), which causes systemd to treat it as a ‘new’ service and reset it to its preset state (which is disabled).
Related Issues
Bugzilla report: #2401676
Workarounds
Just re-enable the service: sudo systemctl enable nftables.service