Ok so for about the last few weeks (maybe a month) edge runs in the background and does not end; as evidenced by ccleaner not cleaning at exit and by microsoft edge processes (12 of them) in task manager background processes.
I've got the right settings, no startup boost, no run extensions in the background (toggled and restarted many times over). Turned off all extensions as that is often a problem in other browsers and edge is now chromium so could befoul it too.
Any other suggestions (outside of don't use edge) I like it and it makes me able to help others who just use the default browser whatever it is.