Braid is a multiplayer web browser

Sign up? I can't just test it and be boxed in an instance with a few other people?

My guess -- this is a multi-session VNC controlling a browser. If not, I'd need to see why it's better than a multi-session VNC

I am not giving my email address to something with a video that doesn't show a single feature.

Is this related to Braid?

https://braid.org/

...what? And why? I am struggling to understand the reason this exsits.