Method 1.Using websocket.org web interface
http://www.websocket.org/echo.html
https://www.websocket.org/echo.html
Method 2. Using curl
curl -i -N \
-H "Connection: Upgrade" \
-H "Upgrade: websocket" \
-H "Host: crm.mage2.pro" \
-H "Origin: https://crm.mage2.pro" \
https://crm.mage2.pro:443