Comment 1 for bug 1646784

This can be reproduced by:
1. Attempting a login, e.g. using Python:
$ python
>>> from gi.repository import Snapd
>>> Snapd.login_sync ("", "", "")
2. Entering your password in the PolicyKit dialog
3. Killing snapd, i.e:
$ sudo killall snapd

Step 1 causes snapd-login-service to start, 2 to make a connection to snapd and 3 to cause the socket to be closed. Because snapd-glib wasn't correctly disabling the socket callback it would be called on a destroyed object.