Websocket - no @OnError handler declared

WARN [2021-10-19 10:49:52,182] ({qtp1276504061-50} org.eclipse.jetty.websocket.jsr356.annotations.JsrEvents#JsrEvents.java[callError]:158) - Unable to report throwable to websocket (no @OnError handler declared): org.apache.zeppelin.socket.NotebookServer
"java.io.IOException: Broken pipe
	at org.eclipse.jetty.io.ssl.SslConnection$DecryptedEndPoint.flush(SslConnection.java:1086)
	at org.eclipse.jetty.io.WriteFlusher.flush(WriteFlusher.java:422)
	at org.eclipse.jetty.io.WriteFlusher.write(WriteFlusher.java:277)
	at org.eclipse.jetty.io.AbstractEndPoint.write(AbstractEndPoint.java:381)
	at org.eclipse.jetty.websocket.common.io.FrameFlusher.flush(FrameFlusher.java:264)
	at org.eclipse.jetty.websocket.common.io.FrameFlusher.process(FrameFlusher.java:193)
	at org.eclipse.jetty.util.IteratingCallback.processing(IteratingCallback.java:241)
	at org.eclipse.jetty.util.IteratingCallback.iterate(IteratingCallback.java:223)
	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.outgoingFrame(AbstractWebSocketConnection.java:581)
	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.close(AbstractWebSocketConnection.java:181)
	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.onFillable(AbstractWebSocketConnection.java:510)
	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.onFillable(AbstractWebSocketConnection.java:440)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
	at org.eclipse.jetty.io.ssl.SslConnection$DecryptedEndPoint.onFillable(SslConnection.java:540)
	at org.eclipse.jetty.io.ssl.SslConnection.onFillable(SslConnection.java:395)
	at org.eclipse.jetty.io.ssl.SslConnection$2.succeeded(SslConnection.java:161)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
	at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:336)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:313)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:171)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:129)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:375)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:806)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:938)
	at java.lang.Thread.run(Thread.java:748)