Comment 6 for bug 1873288

I don't see wireguard-modules as being provided anywhere:

$ apt-cache show linux-image-generic linux-image-5.4.0-24-generic linux-modules-5.4.0-24-generic | grep Provides
Provides: virtualbox-guest-modules (= 6.1.4-dfsg-2), zfs-modules (= 0.8.3-1ubuntu11)
Provides: aufs-dkms, fuse-module, ivtv-modules, kvm-api-4, linux-image, redhat-cluster-modules, spl-dkms, spl-modules, virtualbox-guest-dkms, virtualbox-guest-modules, zfs-dkms, zfs-modules

Only linux-modules-5.4.0-XX-generic has "Built-Using" (dunno how that's used by apt) and it's the package actually shipping the .ko:

$ apt-cache show linux-modules-5.4.0-24-generic | grep wireguard
Built-Using: virtualbox-guest-dkms (= 6.1.4-dfsg-2), wireguard-dkms (= 1.0.20200401-1ubuntu1), zfs-dkms (= 0.8.3-1ubuntu11)

So I think the bug is twofold: 1) the kernel package is missing the "Provides: wireguard-modules" and 2) wireguard-tools "Recommends" ordering needs to have wireguard-modules first as done in Debian.

Something caught my attention:

$ lxc launch images:ubuntu/focal foo --vm
$ lxc exec foo -- apt-get update
$ lxc exec foo -- apt-get install -Vs wireguard-tools | grep wireguard
   wireguard (1.0.20200319-1ubuntu1)
   wireguard-dkms (1.0.20200413-1)
   wireguard (1.0.20200319-1ubuntu1)
   wireguard-dkms (1.0.20200413-1)
   wireguard-tools (1.0.20200319-1ubuntu1)
Inst wireguard-dkms (1.0.20200413-1 Ubuntu:20.04/focal [all])
Inst wireguard-tools (1.0.20200319-1ubuntu1 Ubuntu:20.04/focal [amd64])
Inst wireguard (1.0.20200319-1ubuntu1 Ubuntu:20.04/focal [all])
Conf wireguard-dkms (1.0.20200413-1 Ubuntu:20.04/focal [all])
Conf wireguard-tools (1.0.20200319-1ubuntu1 Ubuntu:20.04/focal [amd64])
Conf wireguard (1.0.20200319-1ubuntu1 Ubuntu:20.04/focal [all])

The wireguard{,-dkms,-tools} versions do not align: wireguard-dkms is newer. Maybe that's not relevant but I thought I'd mention it.