missing guest additions in 20.04 (focal64) virtualbox images

[Carlos Rodrigues]

I'm trying to upgrade my vagrant setup to 20.04 LTS using the virtualbox images available at https://app.vagrantup.com/ubuntu/boxes/focal64 but these seem to be missing the guest additions (required for shared folders, for example).

The guest additions used to be included in the 18.04 LTS images, so this looks like a regression in functionality.

I've tried using the vagrant-vbguest plugin, and that seems to work. However, this is a suboptimal solution as building the guest additions is very brittle in my experience, with updates (either kernel updates, vagrant updates, or virtualbox updates) frequently break it.

[Robert C Jennings (rcj)]

Thank you, we will track this in bug #1873506