Test page prioritizes ping with IPv6 on some devices

Hi team,

Recently, the greencloud-sgn server (IPv6) has a routing error going out internationally and then back to Vietnam. I found that devices that prioritize IPv6 will choose the server (with available IPv6) to test ping.

NextDNS can improve so that ultralow servers that do not have IPv6 (both servers are available) will not ping the IPv6 address to avoid getting incorrect results.

With iOS:

 With PC browser:

 In addition, the routing problem of greencloud-sgn server (IPv6) is also having problems (With ISP Viettel). While IPv4 works fine.