Disable Profile Photo

We’re running an anonymous discussion board, and can’t have people uploading photos of themselves. How can we disable 1) the prompt that displays by default asking new users to add a profile picture and 2) users’ ability to upload a profile picture in the first place. Disabling the setting “Allow uploaded avatars” doesn’t seem to do the trick.

I think you also need to disable gravatars. Search settings for “gravatar”