logout fails...

[Jacques Beigbeder]

Hello Ubuntu users,

I have a new problem with 50 Linux boxes.

My environment:
	Ubuntu 16.04 up to date
	a lot of packages (computers used for teaching)
	Display manager: ligthdm
	User: created with an empty home

The user logs with Ubuntu session, since:
	# cat /etc/lightdm/lightdm.conf
	[SeatDefaults]
	user-session=ubuntu
	greeter-session=unity-greeter
	greeter-show-manual-login=true
	greeter-hide-users=true
	allow-guest=false
	greeter-setup-script=/usr/bin/numlockx on

The problem: when the user tries to logout, it doesn't logout.
Only on the 4th try!

Another problem, in a terminal:
	user> kill -1 -1
doesn't logout, all user process restart.

Another problem: if the user locks the session or try to switch
account, no way to choose a new user: the only prompt in lightdm
is for the password for the locked user..

The problem seems to happen with an update during August. In July,
OK, now fails...

Any idea?

Thanks,

--
Jacques Beigbeder                    |  Jacques.Beigbeder at ens.fr
Service de Prestations Informatiques |     http://www.spi.ens.fr
Ecole normale supérieure             |
45 rue d'Ulm                         |Tel : (+33 1)1 44 32 37 96
F75230 Paris cedex 05                |Fax : (+33 1)1 44 32 20 75