Elon Musk announced that a new version of X's direct messaging feature, XChat, was rolling out with support for features like vanishing messages, encryption, and the ability to share files, alongside its audio and video calling support.

On a help page, X says that XChat is susceptible to "man-in-the-middle attacks", which is someone at X could potentially read your messages without anyone knowing.

Per Musk, XChat (which it appears will simply replace the existing Messages feature) is rolling out with “encryption, vanishing messages and the ability to send any kind of file