(In reply to bert from comment #15) > The problem with detectportal.firefox.com is it's dual stack, so if you're accessing it through a proxy you have no way to tell which protocol was used. It is possible to implement the IPv6 connectivity check on a single dual stack host. That said, the current `http://detectportal.firefox.com/success.txt?ipv6` seems to be broken. It always returns `success` even in IPv4-only network.
Bug 1912610 Comment 16 Edit History
Note: The actual edited comment in the bug view page will always show the original commenter’s name and original timestamp.
(In reply to bert from comment #15) > The problem with detectportal.firefox.com is it's dual stack, so if you're accessing it through a proxy you have no way to tell which protocol was used. It is possible to implement the IPv6 connectivity check on a single dual stack host. That said, the current `http://detectportal.firefox.com/success.txt?ipv6` seems to be broken. It always returns `success` even in IPv4-only network. Edit: I made a test implementation: `https://emk.name/test/ipv6test.cgi`