Facebook has overhauled its approach to harmful Covid-19 health misinformation, announcing major changes that would send a much stronger message to users who have interacted with harmful falsehoods about the virus. … Previously, the social media platform had opted to send users generalized messages informing them that they had interacted with misinformation. But experts said it would be more effective to immediately correct false posts with specific details on why they are inaccurate, an approach that the research suggests can tamp down more sustainably on rampant misinformation in the long run.