Error "Websocket was disconnected, please refresh your browser" in XSOAR GUI

• Repeated occurrences of the error message: "WebSocket was disconnected, please refresh your browser." on GUI 
• Errors in the server logs or Cortex XSOAR’s System Diagnostics page like the message below:

/home/ubuntu/.go_workspace/src/github.com/demisto/server/websockets/wsconn.go:111)
2019-12-12 10:21:12.9289 error write tcp 127.0.0.1:443->127.0.0.1:52181: use of closed network connection

• Cortex XSOAR
• Version 6.1 and later

• The network proxy is killing the WebSocket connection.
• Too much data is being passed on the WebSockets channel; An inadequate buffer size for WebSocket connections

1. If the network proxy is the cause, adjust network proxy settings to allow WebSocket connections.
2. If data size is the cause, increase the buffer size in the server configuration - WebSocket-Configuration
   1. After restarting, clear the browser cache to ensure the session is refreshed.