Again, I don't disagree that CBS has been slacking with this debate, and that tweet was clearly biased. With that said, it DID bring up a very valid concern that many people have with Hillary. Better that she becomes more prepared for answering these questions, when she (likely) faces the GOP in the general election.
Watching the stream online there's a pie chart of how much each candidate is being mentioned on twitter, O'Malley passed 10% for the first time I've noticed after saying "Black Lives Matter."