Websocket Server does not support Sec-WebSocket-Protocol header

[garagegadget]

Hi,

During testing of the IDF 4.2 Websocket example server and establishing connection containing the Sec-WebSocket-Protocol header with a sub-protocol specified the server terminates the connection with log entry
"httpd_ws: httpd_ws_get_frame_type: Failed to read header byte (socket FD invalid), closing socket now"

BR,
Brent