For Tunmbleweed we might simply remove the line with XLIB_SKIP_ARGB_VISUALS=1 as this visual bug is quite old ... nevertheless IMHO this variable should not trigger a crash within gtk+ 3 ... AFAICR GNOME code is using all the time many checks to check every pointer if it is a valid, therefore even if visual I suspect a warning (but no abort() in final packages please).