In reference to the patent: US8918339, it would seem to me that the Path (social network) had this same implementation years before Facebook.
Its been easy to find, via search engines, a number of screenshots from 2012 and earlier that appear to pre-date the patent.
- "With Reactions, Facebook Supercharges The Like Button With 6 Empathetic Emoji". TechCrunch article notes Path image form 2012
- "Path Tries Again With a Wider Network" - NYTimes, Nov 2011, with screenshot
- "Path for Apple iOS, Android: Mobile Social Network Review" - Jan 2012
Wouldn't that be grounds enough to make this patent invalid? Does anyone have more examples?