You must have a really small......screen as all the Avatars I see fully on my 27" imac. Even on a 15 " they are all there. My smallest screen, 13" does what you have posted.
Only problem with that theory Paul is that next to no one expands their browser to full screen like 27" (my screen is 27" too), for one, reading someones comment from left to right across 27" thereabouts is unreadable. My browser is about half that width so I can readily see all other browsers and applications around it on the screen at the same time.
So, what I am trying to say is nearly everyone's avatar is cropped, as near everyone browse's wrong, except me. I browse right.