Thanks for the update, Bill.
I'm working in patch to get this issue fixed, and released to everyone.
After 7.6.1.1 patch here (at UBB) with User info on Top the Avatars are still different sizes
On My Forum I modified .my-avatar (in styles/common.css) to the following and it seemed to solve that issue in Explorer 11
.my-avatar{border-right:6px solid transparent;height:60px;width:60px;}
Bill