$ git clone -n https://src.fedoraproject.org/rpms/gnome-shell-extension-blur-my-shell.git /var/lib/mock/f39-build-1850228-42234/root/chroot_tmpdir/scmroot/gnome-shell-extension-blur-my-shell
Cloning into '/var/lib/mock/f39-build-1850228-42234/root/chroot_tmpdir/scmroot/gnome-shell-extension-blur-my-shell'...
$ git fetch origin 89311417d8c1f05c762bddb0adaba45e7f8c8c2b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-shell-extension-blur-my-shell
 * [new ref]         89311417d8c1f05c762bddb0adaba45e7f8c8c2b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8931141 Update to version 53 (rhbz#2245227)