Mark Zuckerberg and Elon Musk were once poised to fight in a cage match in 2023, before Zuckerberg called it off, saying that Musk was "not serious." Now, the two billionaires have gone from the brink of battle to using each other's technology.

Meta revealed more details of Community Notes, and said that it incorporates the same open-source algorithm that powers X’s crowdsourced feature.

Meta will begin testing its Community Notes feature, which replaces fact-checking with crowdsourced commentary, next week. It relies on X's open-source tech.