Comment 4 for bug 1928674

This requires uploads of grub2 and grub2-{un,}signed to focal to bump the versioned number in the Replaces (grub2-common) and ensure upgrades from bionic to focal get a newer grub-efi-* with the correct lack of conffiles.

> How can you introduce conffiles in grub-efi-amd64 & grub-efi-arm64 which is shared across releases?

By not sharing it across releases.

> That will cause a mess in focal+ then, since it will conflict with grub2-common there.

Not with separate uploads to bionic and focal.

Which is less of a mess than having grub2-common in < focal having to declare a Replaces: on the versions of the grub binaries from grub2 source shipped in those releases.