Comment 7 for bug 1879466

> The way dual-mode works is by co-installing grub-efi-amd64*-signed* and grub-pc

Okay, I see that the -signed package has the grub-install logic in its postinst as well. Thanks for the pointer.

Having /etc/default/grub owned by grub-common seems eminently reasonable, much more so than sharing/passing it between multiple grub-* packages. I hope to see that implemented soon.

Re: grub-pc + grub-efi-amd64, the Conflicts: would still need to be addressed. These are currently written to allow only one GRUB metapackage, instead of taking into account combinations that make sense.