Bug#633652: X-windows programs don't work anymore for root
> # emacs -Q
> g_dbus_connection_real_closed: Remote peer vanished with error: Underlying GIOStream returned 0 bytes on an async read (g-io-error-quark, 0). Exiting.
> # firefox
> GLib-GIO:ERROR:/build/buildd-glib2.0_2.28.6-1-i386-A3fp41/glib2.0-2.28.6/./gio/gdbusconnection.c:2279:initable_init: assertion failed: (connection->initialization_error == NULL)
These both sound like dbus misconfiguration to me. Does something as
simple as "xclock" work?