Hi everyone,

I came across the Firefox preference network.http.http3.sni-slicing, which appears to be related to HTTP/3 and SNI handling. However, I’ve found very little documentation explaining what it actually does.

Could someone with knowledge of Firefox internals or HTTP/3 clarify:

  • What exactly does this setting change in the browser’s behavior?
  • Does it provide any privacy or security benefits?

I’d appreciate any insights. Thanks!

  • ariadna@programming.devOP
    4·
    3 days ago

    @[email protected], @[email protected], thank you for the help and the links — things are a bit clearer now.

    As I understand it, SNI slicing helps obscure the presence of the SNI field in the TLS ClientHello by splitting it into two chunks. The idea, it seems, is to make it more difficult for third-party network filters or DPI systems to detect or extract the SNI reliably.