You can change your gridview element's
IsTabStop
property to false to gain that effect.
Also if you want to cycle with Tab you can
TabNavigation="Cycle"
.
Both changes are in xaml.
Does that happen in all browsers ?
Try setting the IsTabStop property -
http://msdn.microsoft.com/en-us/library/system.windows.controls.control.istabstop.aspx[
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