How does "on.quad9.net" know whether a user is using quad9?
To be able to know if a user is using quad9 by browsing https://on.quad9.net/, I was expecting the same technique as DNS leak test to be used (see How does dnsleaktest.com find my DNS provider).
However, it does not seem like https://on.qu… Continue reading How does "on.quad9.net" know whether a user is using quad9?