The site online-go.com uses WebSockets to connect the browser to its servers. Since a week or so ago, these connections stop responding 20s after they are created and disconnect after another 20s. This happens every time.
It always happens when connecting to an IP6 address, never for IP4 (the site has three of each).
It happens for both the normal online-go.com web client and when mimicking it on a WebSocket test site like websocketking.com. I don't know of it happening when connecting to other WebSocket servers.
Most relevant to this forum, it only happens when connecting from BT's network (which I get from EE). It doesn't happen if I go via a VPN to any other network, nor does it happen for users in other countries.
The servers are fronted by Cloudflare so it looks like WebSocket over IP6 connections from BT to Cloudflare fail as described above.
For more discussion, see: https://forums.online-go.com/t/ogs-connection-issues-for-bt-users-was-is-ogs-running-slow-no-it-isnt....
Obviously, I would expect BT to blame Cloudflare and vice versa so I'm not going to even try to get support but I thought it might help others with the same issue.
