Twitter locked user's account after referencing recent Stanford University study on the numerous health risks of mask-wearing: Twitter locked a user's account after the person referenced a recent Stanford University study claiming masks are ineffective and harmful. Although the user did not document which rules Twitter claimed were violated, the platform told other users who tweeted about the same study that they violated its "policy on spreading misleading and potentially harmful information related to COVID-19." Twitter locked the user's account for 12 hours. Locked accounts can typically use direct messages and browse the platform but cannot tweet, retweet, like other tweets or follow new accounts.