I was under the impression that in iOS 16, Safari will default to using HTTP/3 running over QUIC when connecting to websites, and it will only downgrade to HTTP/2 if the given website does not support HTTP/3. Not all websites support HTTP/3 + QUIC, but certainly the “big ones” do.
Now, it turns out that I’m using Private Relay (PR), so it’s possible that my end to end website connections are indeed using HTTP/3 running over QUIC, but for some reason when you hit an HTTP/3 test website, PR causes the test website to incorrectly report that your browser is using HTTP/2? Can any developers confirm this?
Try as a test:
https://cloudflare-quic.com/
If it’s true that Safari in iOS 16.4.1 is not using HTTP/3 for websites that support it, that would be disappointing. I think(?) Apple definitely mentioned HTTP/3 running over QUIC would be the preferred default, and HTTP/2 would only be used if it’s impossible to use HTTP/3 in a given situation. There are important security and performance benefits to using HTTP/3 running over QUIC.
—>> I really should try some tests with PR turned off, don’t have time now, but will test later and report back.
Now, it turns out that I’m using Private Relay (PR), so it’s possible that my end to end website connections are indeed using HTTP/3 running over QUIC, but for some reason when you hit an HTTP/3 test website, PR causes the test website to incorrectly report that your browser is using HTTP/2? Can any developers confirm this?
Try as a test:
https://cloudflare-quic.com/
If it’s true that Safari in iOS 16.4.1 is not using HTTP/3 for websites that support it, that would be disappointing. I think(?) Apple definitely mentioned HTTP/3 running over QUIC would be the preferred default, and HTTP/2 would only be used if it’s impossible to use HTTP/3 in a given situation. There are important security and performance benefits to using HTTP/3 running over QUIC.
—>> I really should try some tests with PR turned off, don’t have time now, but will test later and report back.
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