Mozilla has begun to roll out a system addon that enables TLS 1.3 in Firefox. Based on bug reports, this addon was launched on April 3rd, 2017 and is being delivered as a silent update to Firefox that will enable TLS 1.3 for 50% of the users who install it. […]

https://www.bleepingcomputer.com/news/software/mozilla-has-started-gradually-enabling-tls-13-in-firefox/