I think this is caused by setting Ctrl-Space as the default shortcut in ibus-setup's default configuration, that's a diff between Ubuntu and Debian because there was problem in switching the input method in Unity (where Super-Space is captured by gnome/unity-settings-daemon). I'll see if we can drop that with recent gnome/unity-settings-daemon updates.
I think this is caused by setting Ctrl-Space as the default shortcut in ibus-setup's default configuration, that's a diff between Ubuntu and Debian because there was problem in switching the input method in Unity (where Super-Space is captured by gnome/unity- settings- daemon) . I'll see if we can drop that with recent gnome/unity- settings- daemon updates.