Build Twitter and Facebook sharing which is mobile compatible.
#2 is fixed in commit 86068fbefae18462d7bf Because of the schedule, I'm not planning on making the popups mobile friendly (#3), and #1 seems low-priority, so I will work on other tasks for now and see if I can get to this later.
Austin and I agree that for this release, it looks like the return on investment for the like button and mobile-friendly popups isn't worth it. Let's spend more time on this later, and see if a better solution presents itself at that time.
verified fixed http://demos.mozilla.org/