Some Sites very slow even with turned off IPv6

[jacob.salmela]

Can you verify this isn't the problem?

Why do some sites take forever to load when using Pi-hole? (for versions < v4.0)

Update: 2018-08-06 As of v4.0, this should no longer be a problem unless you choose to deviate from the new default blocking mode and return to the IP-based mode. And the iptables rules mentioned in this article should not be needed. Update As of v3.1 the first reason should not be an issue anymore That being said, there are generally two reasons this happens: your ISP changes your IPv6 address (Global Unicast Address), causing Pi-hole to become misconfigured and timing out when trying…