Comment 5 for bug 1637758

What do you mean with current zesty? I just installed all updates (I don't use proposed), but I have not restarted pc and/or lightdm...

If /usr/lib/lightdm/lightdm-greeter-session has this line:
eval `dbus-launch --sh-syntax`

Then my second seat / session works - I can logout & login without problems.

When I restore this line:
[ -n "$DBUS_SESSION_BUS_ADDRESS" ] || eval `dbus-launch --sh-syntax`

Problem is back. Every time I try to login unity-settings-daemon started from lightdm is still running...

alberts@ga-b75m-d3h:~$ loginctl
   SESSION UID USER SEAT TTY
        c4 1001 flashback seat1
         2 120 debian-spamd /dev/pts/8
       c42 1001 flashback seat1
        c3 1000 alberts seat0
       c43 111 lightdm seat1
       c44 1001 flashback seat1

6 sessions listed.

alberts@ga-b75m-d3h:~$ loginctl session-status c43
c43 - lightdm (111)
           Since: Tue 2016-11-08 18:16:59 EET; 2min 3s ago
          Leader: 20942
            Seat: seat1
         Display: :0
         Service: lightdm-greeter; type x11; class greeter
           State: closing
            Unit: session-c43.scope
                  ├─20972 /usr/lib/at-spi2-core/at-spi2-registryd --use-gnome-session
                  ├─20983 nm-applet
                  └─20985 /usr/lib/unity-settings-daemon/unity-settings-daemon

nov 08 18:16:59 ga-b75m-d3h systemd[1]: Started Session c43 of user lightdm.
nov 08 18:16:59 ga-b75m-d3h org.a11y.atspi.Registry[20970]: SpiRegistry daemon is running with well-known name - org.a11y.atsp
nov 08 18:17:03 ga-b75m-d3h lightdm[20942]: pam_unix(lightdm-greeter:session): session closed for user lightdm