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Firefox not using HTTP3 when HTTP3 is enabled on that site.

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  • Last reply by Alvin

Alvin
Alvin
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I visited https://cloudflare-quic.com/ and it said my browser used HTTP/2 when loading that page. Devtools also said is load with HTTP/3 protocol. `network.http.http3.enabled` is true in about:config

I visited https://cloudflare-quic.com/ and it said my browser used HTTP/2 when loading that page. Devtools also said is load with HTTP/3 protocol. `network.http.http3.enabled` is true in about:config

All Replies (2)

Alvin
Alvin Question owner
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Turns out is because `network.dns.disablePrefetch` is true, by setting that to false fixed the issue.

Alvin
Alvin Question owner
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Alvin said
Turns out is because `network.dns.disablePrefetch` is true, by setting that to false fixed the issue.

That might not be the direct cause of this issue, it works for the first time but after you restart the browser the issue persists.