When starting yast2 on Gnome3 with Wayland session it just segfault with below log from systemd-journal:

 maj 28 22:31:59 green gnomesu-pam-backend[6755]: The gnome keyring socket is not owned with the same credentials as the user login: /run/user/1000/keyring/control
maj 28 22:31:59 green gnomesu-pam-backend[6755]: gkr-pam: couldn't unlock the login keyring.
maj 28 22:31:59 green gnomesu-pam-backend[6755]: pam_unix(gnomesu-pam:session): session opened for user root by (uid=1000)
maj 28 22:31:59 green YaST.desktop[5395]: No protocol specified
maj 28 22:31:59 green YaST.desktop[5395]: No protocol specified
maj 28 22:31:59 green YaST.desktop[5395]: qt.qpa.xcb: could not connect to display :0
maj 28 22:31:59 green YaST.desktop[5395]: qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
maj 28 22:31:59 green YaST.desktop[5395]: qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
maj 28 22:31:59 green YaST.desktop[5395]: This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
maj 28 22:31:59 green YaST.desktop[5395]: Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.
maj 28 22:31:59 green YaST.desktop[5395]: /sbin/yast2: line 461:  6778 Aborted                 (core dumped) $y2ccbin $Y2UI_ARGS "$@"

This is directly after a clean install with default settings for Gnome3 on Tumbleweed snapshot 20190527

I tested to login with Xorg and there it works as expected.