[opensuse-factory] NetworkManager fails to offer Bridge

I have several root partitions. With TW XFCE the NetworkManager GUI allows me to add a bridge. With TW GNOME/KDE the GUI allows just some sort of VPN. I compared package lists in each one, there is no obvious difference. All 'rpm -qa | grep -i netwo' gives similar results, bridge-utils is also installed. Does anyone happen to know how NetworkManager GUI decides when 'Adding Bridge..' is supposed to be shown? Olaf