Description of problem:
Using fdi.vlan.primary parameter creates a broken NetworkManager configuration:

In the section VLAN, a new line expression is not evaluated properly:

/etc/NetworkManager/system-connections/primary
[connection]
id=primary
type=vlan
autoconnect=true
autoconnect-priority=1
[802-3-ethernet]
mac-address=00:a0:10:01:d5:ab
[ipv4]
method=auto
dhcp-send-hostname=false
dhcp-timeout=300
[ipv6]
method=auto
[vlan]\nid=10 <===