...

# You should have received a copy of the GNU General Public License
# along with GRUB.  If not, see <http://www.gnu.org/licenses/>.

# Akua - grubenv doesn't survive on ZFS
GRUBENV="(hd0,msdos1)/grubenv"

...

if [ "x${GRUB_TIMEOUT_BUTTON}" = "x" ] ; then
GRUB_TIMEOUT_BUTTON="$GRUB_TIMEOUT" ; fi

cat << EOF
# Akua - grubenv doesn't survive on ZFS
grubenv="$GRUBENV"

# Akua
if [ -s "${grubenv}" ]; then
  set have_grubenv=true
  # Akua
  load_env --file "${grubenv}"
fi

...

 akua@blackbird:~ 09:08 /
 $ grep grubenv /etc/grub.d/00_header
# Akua - grubenv doesn't survive on ZFS
GRUBENV="(hd0,msdos1)/grubenv"
# Akua - grubenv doesn't survive on ZFS
grubenv="$GRUBENV"
if [ -s "${grubenv}" ]; then
  set have_grubenv=true
  load_env --file "${grubenv}"
   save_env --file "${grubenv}" prev_entry
   save_env --file "${grubenv}" next_entry
   save_env --file "${grubenv}" next_entry
  save_env --file "${grubenv}" saved_entry
  save_env --file "${grubenv}" prev_saved_entry
save_env --file "${grubenv}" saved_entry
    if [ -n "${have_grubenv}" ]; then if [ -n "${partuuid}" ]; then
      save_env --file "${grubenv}" prev_entry
  save_env --file "${grubenv}" initrdfail
  if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env --file "${grubenv}" recordfail; fi; fi