I have noticed that Community ♦ user's avatar had changed yesterday on Gamedev.se.
(Not that I mind, but the new avatar is harder to spot because it blends in with other new users' avatars.)
Then I clicked on the avatar to consult the profile, and it was the same old, usual avatar.
So there are two different avatar images: one used in the feed, and one used in the profile.
I guess it's a bug?
I have noticed the same behaviour on Stack Overflow too.
Screenshot of the avatar in the question feeds:
Screenshot of the avatar on the profile: