What's kind of annoying is that Ubuntu has moved most of the system from upstart to systemd, but user sessions are still managed by upstart. If I want to custom

What's kind of annoying is that Ubuntu has moved most of the system from upstart to systemd, but user sessions are still managed by upstart. If I want to customize my user sessions, I need to learn how to use a system that's being phased out and is incompatible with the rest of the world.