It seems a recent changed caused the "newest" and "next" badges' icons to be cut off on user's activity pages. The behavior below can be seen on UX.SE, GD.SE, Physics.SE, and all others that I checked besides SO and Meta.SE.
Thanks for taking the time to report this. This has been corrected and will be updated with the next prod build.
The issue affected all network sites, though it may have appeared to only affect some. This is because some community badges are about the same size as the default Stack Overflow badges (7px). Some, such as UX.SE and GD.SE, are larger (14px).