update instructions re using websockets via nginx
@@ -87,7 +87,8 @@ This is slightly more "raw", but supports things like chunked input.
* Haproxy works fine.
-* nginx >= 1.4 works fine and without additional configuration.
+* nginx needs a special location setting to correctly pass the HTTP Upgrade and Connection headers: https://nginx.org/en/docs/http/websocket.html
+
Language support
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