This bug was fixed in the package grub2-signed - 1.66.9
--------------- grub2-signed (1.66.9) xenial; urgency=medium
* Rebuild against grub2 2.02~beta2-36ubuntu3.8. (LP: #1637290)
-- Mathieu Trudel-Lapierre <email address hidden> Thu, 23 Mar 2017 16:22:31 -0400
This bug was fixed in the package grub2-signed - 1.66.9
---------------
grub2-signed (1.66.9) xenial; urgency=medium
* Rebuild against grub2 2.02~beta2- 36ubuntu3. 8. (LP: #1637290)
-- Mathieu Trudel-Lapierre <email address hidden> Thu, 23 Mar 2017 16:22:31 -0400