I did some additional debugging on this and found the file `/run/NetworkManager/conf.d/netplan.conf` with contents:
[keyfile]
# devices managed by networkd
unmanaged-devices+=interface-name:enp1s0
Removing that file leads to the device being listed as managed by `nmcli d status`, but this file get's created again every reboot by netplan, so it does not hold for long. (And then the device is unmanaged again)
I did some additional debugging on this and found the file `/run/NetworkMa nager/conf. d/netplan. conf` with contents: devices+ =interface- name:enp1s0
[keyfile]
# devices managed by networkd
unmanaged-
Removing that file leads to the device being listed as managed by `nmcli d status`, but this file get's created again every reboot by netplan, so it does not hold for long. (And then the device is unmanaged again)