Mozilla engineers have activated support for TLS 1.3 in the latest version of Firefox 49, also known as Firefox Developer Edition.

TLS 1.3 is the latest version of the TLS protocol, a crucial part of running websites via HTTPS. The protocol was announced this January, when the Internet Engineering Task Force (IETF) started working on an official draft. The final version is expected to become an official RFC this summer.

As the protocol started to shape up, this past February, Mozilla's engineers began work on integrating it into their browser. The feature was given the green light this month and is now live with the current Firefox Developer Edition.

TLS 1.3 support is not on by default, and in order to access sites using TLS 1.3 encryption, you'll need to turn it on by typing about:config in your browser URL bar, searching for the security.tls.version.max setting and entering 4 in the Value field.

Of course, since TLS 1.3 isn't officially released, there aren't that many sites using it anyway. Nevertheless, it's encouraging to see Mozilla's staff keeping up with the latest updates regarding encryption.

The stable version of Firefox 49 is scheduled for September 13, 2016. This is the same version that will feature a fully working implementation of the WebExtensions API and have full e10s (Electrolysis) support.

TLS 1.3 is also supported in Microsoft's Edge browser but is currently available only for Windows Insider Preview builds running Edge version 14.14361 and higher.