$ git clone -n https://src.fedoraproject.org/rpms/gnome-shell-extension-pop-shell.git /var/lib/mock/f39-build-1869062-42616/root/chroot_tmpdir/scmroot/gnome-shell-extension-pop-shell
Cloning into '/var/lib/mock/f39-build-1869062-42616/root/chroot_tmpdir/scmroot/gnome-shell-extension-pop-shell'...
$ git fetch origin 3a61e6b64077a06a7dc398d18670084958308748:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-shell-extension-pop-shell
 * [new ref]         3a61e6b64077a06a7dc398d18670084958308748 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3a61e6b Update to new upstream snapshot for improved GNOME 45 support