Set larger socket timeout (or 0 to set no timeout).
Upgrade your nanohttpd
Here is a animation for the life cycle. http://tcp.cs.st-andrews.ac.uk/index.shtml?page=connection_lifecycle
Upgrade your docker-selenium
Client closed the websocket connection (safe to ignore)
Nginx does not handle websocket requests. Configure nginx proxy for websockets.
It takes too long time for the JVM to find enough entropy for secure connection. Use this jvm option: '-Djava.security.egd=file:/dev/./urandom'.
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