Cite as: 601 U. S. ____ (2024) 15 Opinion of the Court which Lindke objected: He deleted Lindke’s comments and blocked him from commenting again. So far as deletion goes, the only relevant posts are those from which Lindke’s comments were removed. Blocking, however, is a different story. Because blocking operated on a page-wide basis, a court would have to consider whether Freed had engaged in state action with respect to any post on which Lindke wished to comment. The bluntness of Facebook’s blocking tool highlights the cost of a “mixed use” social-media account: If page-wide blocking is the only option, a public official might be unable to prevent someone from commenting on his personal posts without risking liability for also preventing comments on his official posts.3 A public official who fails to keep personal posts in a clearly designated personal account therefore exposes himself to greater potential liability. * * * The state-action doctrine requires Lindke to show that Freed (1) had actual authority to speak on behalf of the State on a particular matter, and (2) purported to exercise that authority in the relevant posts. To the extent that this test differs from the one applied by the Sixth Circuit, we vacate its judgment and remand the case for further proceedings consistent with this opinion. It is so ordered. —————— 3 On some platforms, a blocked user might be unable even to see the blocker’s posts. See, e.g., Garnier v. O’Connor-Ratcliff, 41 F. 4th, 1158, 1164 (CA9 2022) (noting that “on Twitter, once a user has been ‘blocked,’ the individual can neither interact with nor view the blocker’s Twitter feed”); Knight First Amdt. Inst. at Columbia Univ. v. Trump, 928 F. 3d 226, 231 (CA2 2019) (noting that a blocked user is unable to see, reply to, retweet, or like the blocker’s tweets).