@liaizon @drq interesting. I'm now curious which fields of the actor change when you change the username.
I, for one, don't myself do any webfinger requests at all (yet — I'll have to when I'll have search). The "id" URI is *the* identifier for me. As long as that doesn't change, everything else is just semantics. That's why I want to use numeric IDs (/users/234) for those as I already use them extensively internally.