Encrypt that SNI: Firefox edition

What this post added

This post details the implementation and user-facing enablement of Encrypted Server Name Indication (ESNI) in Firefox, in collaboration with Mozilla. It provides instructions on how to enable ESNI in Firefox Nightly via `about:config` and how to verify its functionality using the `encryptedsni.com` test page. It also touches upon the necessity of DNS over HTTPS (DoH) for complete privacy and discusses potential fallback mechanisms and challenges in ESNI key management and synchronization between DNS and TLS servers.