20.04: disabling restart and poweroff

[Jacques Beigbeder]

Hello,

In classrooms, I want to disable restart and poweroff.
First on lightdm screens,
then when a user is logged on.

I already setup
	/usr/share/glib-2.0/schemas/10_ubuntu-settings.gschema.override
so now 'dbus-launch list-recursively ...' displays:
  org.gnome.settings-daemon.plugins.power power-button-action 'nothing'
  org.gnome.settings-daemon.plugins.power button-power 'nothing'
  org.gnome.login-screen disable-restart-buttons true

Activating power button, clicking on Quit upper-right screen
still displays 'restart'.

Any answer?
Thanks,

--
Jacques Beigbeder                    |   Jacques.Beigbeder at ens.fr
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