The solution in https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1814187/comments/3 fixed this for me. Not sure if this should be marked as a duplicate of that issue, since it is for grub-efi-amd64, not grub-efi-amd64-signed?
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1851030 Title: grub-efi-amd64-signed failes to install/upgrade - exit status 127 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2-signed/+bug/1851030/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
