$ git clone -n https://src.fedoraproject.org/rpms/Thunar.git /var/lib/mock/f39-build-2186574-51358/root/chroot_tmpdir/scmroot/Thunar
Cloning into '/var/lib/mock/f39-build-2186574-51358/root/chroot_tmpdir/scmroot/Thunar'...
$ git fetch origin e1e4239fe1b27c00d50a0703cafd6e303d87fd15:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/Thunar
 * [new ref]         e1e4239fe1b27c00d50a0703cafd6e303d87fd15 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e1e4239 Update to v4.18.10