This is how the Ajax client solves now when multiple tab rows used in a browser didn't allow to show the contents, in order to make a cleaner interface for both browsers in desktop/laptops and mobile. You can hide all tabs with this extension: http://community.qlik.com/docs/DOC-4236, but apart from that you cannot choose to show several rows or only one.
Note that the IE Plugin behaves different because it is basically the thick client (QlikView Desktop). So expect to see in Plugin exactly the same to what you see in Desktop.
Hope that makes sense.