Yeah the spec is at https://webxdc.org/ and it is implemented by Delta Chat and a couple XMPP clients.

I don’t use Matrix so I’m not sure.

simple to use

• share a webxdc zip file in your chat
• ???
• profit

Not sure how to make that simpler

big accounts won’t move over, nor will their followers.

This post is about private messaging, not social media.

They are apps that use a messenger as backend, so basically your conversation with someone else has all the state of the webxdc. In Delta Chat that would be the encrypted email thread.

To use a webxdc share it in any of the mentioned messaging apps.