InfoPath: add Tab index to the control
SharePoint: Script Editor web part
SharePoint: copy-n-paste code into a Script Editor
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$('a[tabindex="11"]').each(function() {
$(this).attr('target', '_top');
});
});
</script>