KDE Neon allows you to test the full desktop as a docker image that runs the full OS in a window. It can also start an application of the docker image in a separate window as explained in https://community.kde.org/Neon/Docker.
Can Kubuntu or Ubuntu do this? I have found docker-ubuntu-vnc-desktop and https://stackoverflow.com/questions/31446661/build-a-full-ubuntu-desktop-docker-image but it’s not the same.
It would be nice to test any Ubuntu flavour with a one line command but even if it’s just Kubuntu, which uses KDE too, it would be useful.