Yes Jean-Michel, although technically not correct (because I do "have" them), you could say that.
Technically correct would be to say that the buttons do not change their Qt property responsible to take them out of a disabled state:
powerButton {
enabled: sddm.canPowerOff
}
But the issue is with the internals of SDDM not setting this boolean on my system and I don't know why.
As a further note: my system is based on a minimal installation. So maybe I'm missing some dbus connector? dbus-user is for users,...SDDM is a root application, so I guess I can discard that one. As mentioned I have pm-utils installed to make KDE connect the power functions that would usually be provided by systemd calls, but SDDM is a separate program. I'm on a loss.
My root tree is rather basic:
root
Initialized: yes | Current: yes
Contains: | Enabled: yes
├─(980,Enabled,longrun) dbus-log
├─(950,Enabled,classic) tty1
├─(951,Enabled,classic) wpa_supplicant-log
├─(979,Enabled,longrun) networkmanager-log
├─(952,Enabled,classic) tty2
├─(0,Enabled,classic) wpa_supplicant
├─(961,Enabled,longrun) scandir-marian
├─(984,Enabled,longrun) dbus
├─(978,Enabled,longrun) sddm-log
├─(992,Enabled,longrun) sddm
└─(993,Enabled,longrun) networkmanager