Do not recommend block_ipv6

jedisct1 · jedisct1 · commit 1c80e80a0d0a · 2018-01-21T00:54:20.000+01:00
diff --git a/dnscrypt-proxy/dnscrypt-proxy.toml b/dnscrypt-proxy/dnscrypt-proxy.toml
@@ -85,7 +85,9 @@ cert_refresh_delay = 30
 #########################
 
 ## Immediately respond to IPv6-related queries with an empty response
-## This makes things faster when there is no IPv6 connectivity
+## This makes things faster when there is no IPv6 connectivity, but can
+## also cause reliability issues with some stub resolvers. In
+## particular, enabling this on macOS is not recommended.
 
 block_ipv6 = false
 
