Worth mentioning Jess Frazelle was running desktop applications in docker a while ago. Not a full desktop, but also quicker to rebuild individual apps.

https://blog.jessfraz.com/post/docker-containers-on-the-desk... https://github.com/jessfraz/dockerfiles

I've been running stuff in LXC for ages (and before that, custom chroots). A while ago I made the switch to Wayland - and now started moving things over to podman, which has the added benefit of being able to share the stuff easily:

https://github.com/aard-fi/tumbleweed-images/tree/master/way...

I use two different setups - on some systems I only run things like browsers in conatainers, on others I also run the desktop itself in a container. Not published yet are my helper scripts, that'll need some more cleaning up.