I would have expected that after these steps in pre_umount_finish https://github.com/yast/yast-installation/blob/master/src/lib/installation/clients/pre_umount_finish.rb#L56-L62 zypp should be gone. Otherwise I don't see where else it should come from considering our workflow: https://github.com/yast/yast-installation/blob/master/src/lib/installation/clients/inst_finish.rb#L494-L497