Please copy/paste messages as text. It is easier and they become searchable.
This is innocent. Typically this is caused by a browser that aborts some connection (for example when switching from a page or reloading a page before the load is finished) before the TLS handshake is completed.
Possibly these should be suppressed, although such messages can be helpful if some client fails to connect.
these below are the messages in text from the swi prolog console for this subject,
I created a web server on ubuntu with swi-prolog as data server, and also
I implemented the chat-server on the site through the swi websocket examples
it took me a few days to get everything working, therefore i was offline,
Broken pipe means the other end (browser) closes the connection unexpectedly. In the context of web sockets this typically indicate you close the websocket (leave the page) without doing the websocket close sequence. Another reason for this message is a network error.
The latter is fully harmless. The former can be avoided by nicely closing the websocket.