Package: ibus Version: 1.4.1-6 ibus-ui (included in ibus package) need certain GNOME/GTK icons to start up. https://bugs.launchpad.net/ubuntu/+source/ibus/+bug/854333 But it is not treated as dependency currently. http://packages.debian.org/sid/ibus So users may encounter strange error in non-GNOME/GTK environments.