A strange technical thing, helping to write more advanced styles (and probably JS) for FB. Overlays the data-ft attribute on things. If you don't know, what this is, you probably don't need this style. ;)

If you want to know: it's something thah lets you select (in CSS) posts by a certain person, or of certain type. For example, if you want to make a style that highlights status updates of certain people, you need to know appropriate data-ft strings.