In template vw-title.css you have too many zeros in the border-bottom on the titleBox.
As for the REAL bug, the editor is not updated when a user makes a "minor" edit. Since you have not made non-minor edits on that page since you upgraded from 2.5.x, I believe this was a bug with 2.5.x that was fixed with the changes to the system made in 3. Unfortunately, the last edit info will continue to be broken until someone makes a REAL edit.