Karissa Bell, at Engadget:
The update adds voice and video calling, file sharing and the ability to edit and delete previously sent messages, as well as privacy-focused features like end-to-end encryption and screenshot notifications.
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X also states that "we do not offer protections against man-in-the-middle attacks," which could compromise an encrypted chat. "As a result, if someone—a malicious insider or X itself as a result of a compulsory legal process—were to compromise an encrypted conversation, neither the sender or receiver would know," the company explains. X says it's working on features that will help users verify the authenticity of encrypted conversations.
Those statements are contradictory: end-to-end encryption means that only the sender and recipient can view the plaintext messages. If a man-in-the-middle—including X itself—can read it, it’s not E2EE.
X is finally rolling out Chat, its DM replacement with encryption and video calling
X has finally revealed its long-promised chat platform, which replaces the service's basic DM functionality with features more like the messaging capabilities on other mainstream apps.