See https://github.com/projectatomic/rpm-ostree/issues/1435 and https://github.com/projectatomic/rpm-ostree/issues/1542#issuecomment-419684977
see https://pagure.io/workstation-ostree-config/pull-request/105
i just tested this on a f29 atomic host compose and it works fine.
Pull-Request has been merged by jlebon
did this in f29 too: https://pagure.io/fedora-atomic/c/075cdd9e63193c2c1aaece5165f118feddb30bc1?branch=f29
See https://github.com/projectatomic/rpm-ostree/issues/1435
and https://github.com/projectatomic/rpm-ostree/issues/1542#issuecomment-419684977