Currently, all profile pictures selected as "main" are public, regardless of the visibility options set by the user. The main profile picture will also stay even if it was deleted from the list with no way of actually removing it (the main profile picture is still visible, even though when viewing the list it is empty). It would be great if I could delete my profile picture or if the visibility options were respected such that, for example, only people I liked can see my main profile picture. There was also no warning that main profile pictures are always public even though I set the visiblity to "liked by me".