Pascal, You could try some ancorgs repository added for the installer self updating and related to the DVD update issues (see https://bugzilla.suse.com/show_bug.cgi?id=1094749#c21) So basically the repo is here: https://download.opensuse.org/repositories/home:/ancorgs:/test_self_update:/Leap_15.0/openSUSE_Leap_15.0/