One of the most powerful tools on social media is the "block" feature. It allows a social media user to silence the haters and drown out the critics, while curating a more friendly social media feed. But after the U.S. Supreme Court decisions in Lindke v. Freed and O'Connor-Ratcliff v. Garnier, public officials across the country may have just lost their most powerful social media tool—and litigation is surely to follow.