That is the long-time-no-see warning when started a PM to an user that hasn’t visited over 30 days.
But that user is an AI-persona. And that happens with only with this one.
I reckon this comes from one idiotic action I did some times ago. I added that as an user to private group chat. At that time my goal was give ability to mention AI if needed. Well, that wasn’t such good idea, because it answered to everyone all the time.
But an admin can’t kick out an user from group chats, but that user must do it, and an AI persona can’t. So, I impersonated it, say goodbye to group chat, logged out and everything was happy and sunny again, and the globe was even more rounded.
Three things happened, though.
- AI persona has now last visited IP
- AI persona has now last visited date
- Some update triggered long-time-no-see action (actually it started exacly same time than this: AI personas aren’t changing as expected when PM
I don’t think this would be a pure bug, because there is really big chance it was born because of me. But I know I’m not the only one, because the question of how to drop an AI from group chat has asked and I guided that impersonating trick 
So:
- can I do something to fix that (other than deleting that pseudo-user and re-creating it)
- is there something on code level that could stop this happening in the future
Not a major issue, sure. That warning is just annoying.