How to test HTTP/3 and QUIC with Firefox Nightly

On June 30, 2020, Lucas Pardue discussed HTTP/3, the latest version of the Hypertext Transfer Protocol that uses QUIC as its transport protocol for improved performance and security. Cloudflare enabled QUIC and HTTP/3 support on their edge network during their Birthday Week in 2019, with support from Google Chrome and Mozilla Firefox. Enabling HTTP/3 for a domain requires flipping the switch in the Cloudflare dashboard's "Network" tab. To test HTTP/3 using Firefox Nightly, users can download and install the latest build, enable HTTP/3 by setting "network.http.http3.enabled" to true, and check the Developer Tools "Protocol" column in the "Network" tab. The QUIC Working Group recently announced a milestone towards standardization, with all design issues resolved or proposed for resolution. Implementations are expected to improve their support for HTTP/3 and eventually enable it in stable channels.