Curiously half of what you're describing has already existed on the web for more than 20 years, in the form of server side push using the obscure `multipart/mix

Curiously half of what you're describing has already existed on the web for more than 20 years, in the form of server side push using the obscure `multipart/mixed` HTTP content type [1]. This technology was added to Netscape in 1995 and I believe it's still supported by modern browsers, but it seems to have hardly gotten much traction beyond those early webcam sites that an image every N seconds. I am not sure if interaction is possible as part of the mix using some tricks, though. It seems like we just have turbolinks for that. [1]: https://docstore.mik.ua/orelly/web2/xhtml/ch13_03.htm https://docstore.mik.ua/orelly/web2/xhtml/ch13_03.htm