EDIT:
Anyway, I noticed if I set firefox to use DOH (cloudflare), firefox tends to connect using ipv4 first.
I had set :
network.trr.early-AAAA to true
network.http.fast-fallback-to-IPv4 to false
and of course, network.notify.IPv6 to true.
Is this a bug or what?
However, after I run firefox for like 20 minutes or so, firefox will connect via ipv6 just fine.
Once i close firefox and re-execute firefox, firefox will connect via ipv4 again.
From what I can tell it's basically whether or not to ask the OS to notify FF on a network interface change (i.e. IPv6 address assignment / connectivity change) and was disabled in bug 1245059 for windows due to at least Windows 10 having issues with its Teredo Tunneling Adapter frequently vanishing and triggering bogus notifications and thereby causing connection timeouts in FF. More information here.
Regarding your edit I would also expect IPv6 preference under those conditions.
johnp_ wrote:From what I can tell it's basically whether or not to ask the OS to notify FF on a network interface change (i.e. IPv6 address assignment / connectivity change) and was disabled in bug 1245059 for windows due to at least Windows 10 having issues with its Teredo Tunneling Adapter frequently vanishing and triggering bogus notifications and thereby causing connection timeouts in FF. More information here.
Regarding your edit I would also expect IPv6 preference under those conditions.
If I don't use DOH, firefox will prefer ipv6 connection right away.
Oh well, I don't exit firefox that often.........
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