Thanks Aohan but still nothing.

At the browser I trigger ws.close()

At the server the web socket class' Server method executes quitting with $$$OK the  OnPostServer method does not execute.

Closing the connection from the server end by invoking the web socket object's EndServer method results in the OnPostServer method executing.

Maybe of importance, the websocket is asynchronous so when triggered from the browser's .close() the Server method is not invoking the EndServer method.