Support for QUIC and HTTP / 3 has been officially announced for Firefox Nightly and Beta build, and will be officially released with the upcoming firmware release of Firefox 88.
HTTP/3 as a new HTTP protocol standard based on QUIC starts rolling out to Firefox. It aims to offer better performance and reliability on the web, but of course it also requires some web compatibility server.
Google and Facebook are among the most important web destinations that already support HTTP / 3.
Mozilla's Dragana Damjanovic announced on the blog on Friday mozilla hacks,
“Support for QUIC and HTTP/3 is now enabled by default in the Firefox Nightly and Firefox Beta channels. We plan to start with the release in the Firefox version Stable Release 88. HTTP/3 will be available by default by the end of May.”
Firefox 88 is expected to be released on April 19.