The W3C has released the first draft of the WebTransport specification, which defines a protocol and accompanying JavaScript API for sending and receiving data between a browser and a server. The communication channel is organized over HTTP / 3 using the QUIC protocol as a transport, which, in turn, is an add-on over the UDP protocol that supports multiplexing of several connections and provides encryption methods equivalent to TLS / SSL.
WebTransport can be used instead of the WebSockets mechanism, offering additional features such as multithreading, unidirectional flows, out-of-order delivery, reliable and unreliable delivery modes. In addition, WebTransport can be used instead of the Server Push mechanism, which Google has deprecated in Chrome.
Source: opennet.ru