$ git clone -n https://git.centos.org/rpms/thunderbird /var/lib/mock/dist-c8-updates-build-73553-23865/root/chroot_tmpdir/scmroot/thunderbird
Cloning into '/var/lib/mock/dist-c8-updates-build-73553-23865/root/chroot_tmpdir/scmroot/thunderbird'...
$ git reset --hard 45d49c493771e5bc21f2a53762358ce1e8c777c5
HEAD is now at 45d49c4 enable openpgp support for thunderbird, try3