There seems to be a bug with my iMessage on my Mac that virtually all the avatar / profile pics had disappeared. Discussing with the genius, we thought that getting rid of the contacts in the address book might resolve it - as possibly a reboot. He left me to manually remove all the duplicates whilst he went on to help other people - but he was happy for me to stay and do this. After removing the duplicates and rebooting the photos did not appear. The Genius was busy at this point. So I was playing around, and then I thought I’d try opening the photos in the address book and re-saving them. This was a master stroke, as the photos suddenly appeared in iMessage. So it was just a case of going through and re-saving all the photos in Contacts and this resolved the problem. Well almost; one message thread still didn’t contain photos when I opened the thread. But scrolling up and scrolling back down the pictures reappeared. So that is kind of a workaround for now, until Apple fix this.
