While Ubuntu is not currently using Wayland by default with its GNOME Shell desktop and it doesn’t look like they will try again until Ubuntu 20.10, the option is still available and they continue working in the direction of a Wayland Linux desktop future. One of their interesting “upstream” contributions in this area is with the Wayland Conformance Suite.
As part of their Wayland interests and namely as part of developing Mir now with Wayland support, for a while they have been working on the “Wayland Conformance Suite” for testing the Wayland protocols for conformance to the specifications. This is for ensuring Wayland compositors behave correctly against the intentions of the protocols.
This morning, Canonical developer Chris Halse Rogers released the Wayland Conformance Suite 1.0. In its current state there are roughly 300 tests to vet Wayland surface events, the Wayland Shell protocol, XDG-Shell, and other areas. They will continue adding tests as Mir’s Wayland support is further extended.