Investigate latency effect on websocket

[Terkwood]

I wonder if a high latency is causing #513. We could investigate this in a couple of ways:

• purchase a VPN and route requests thru it
• deploy a test instance of gateway to a faraway land

Additionally, it would be nice if the browser could somehow report latency metrics to the backend, so that we can understand whether failure events seen in #513 coincide with high latency

[Terkwood]

It can still fail from an Azure server in USA. The websocket is flaky under a variety of circumstances! 😵