im in plasma-git, it tag 5.21-beta i believed.
so, anyone try systemd boot success, or how to?
I am booting with systemd but using 5.20.5. What is broken?
He means, that Plasma 5.21 is now utilizing systemd to launch the session, which should result in faster login times. 
Well, I had to take a look, so I updated to plasma-git. I selected the Prefer lower latency compositor setting, and I like what I see.