I have already hidden the "Facebook join date" from my timeline (by hovering over it, selecting edit or remove (the pencil) and then Hide it from timeline). Right now, I cannot see this date if I go to my timeline and scroll down to the beginning. That makes sense. However, when I view my profile as public (by clicking the blue downward arrow just beside the Activity Log and then selecting "view as"), this "Facebook joining date" is still visible to everyone.
Is that a bug? If not, how can I hide or delete it?