This has happened a few times while reading threads. It is where users posts show up under one users post. See image. See there is the first post, then the second one right bellow it. Then the post for the second one shows up bellow without the avatar. Don't know if this was reported or not. It has done this to me in a few different machines running different OS's. Mac, XP, W7 32 & 64. So i tought i would post it on here to see if it is or not.