Preferred Notebook Style in My Preferences - Sm 9.4x

I am using the 9.4x web client.  When I go into My Preferences and select Preferred Notebook Style -

                   There are 2 values: Tabs & Groups.

Just wondering how this is supposed to work as formats designed with groups never change to Tabs and vice-versa. I tried both preferences and logged off and back to no avail.

How does this preference automatically change format style - is there something we must do when we create the format for this to work.