So Facebook can't use the thumbs up emoji as a button label any more?
Or is that OK because it's an "image", not an "emoji", despite carrying the exact same meaning as the emoji, and looking indistinguishable from a rendering of the emoji?
Or is it OK if they bring their own image file? What if they bring their own emoji font and use that, to improve rendering speed?
User enters emoji in their secret diary: great. You allow selection of mood for today by displaying a range of emoji faces: bad