Web clients connected through WebSocket are randomly disconnected from artemis broker without notification of the disconnection.

A ConcurrentModificationException is raised;

[2021-09-28 10:26:53,591] - [WILDFLY] - [WARN ] - Thread-11 ([ActiveMQ-server-org.apache.activemq.artemis.core.server.impl.ActiveMQServerImpl$6@444dc7ba - [org.apache.activemq.artemis.core.server] : AMQ222151: removing consumer which did not handle a message, consumer=ServerConsumerImpl [id=1990, filter=null, binding=LocalQueueBinding [address=jms.topic.defended_assetFull, queue=QueueImpl[name=d1586796-2035-11ec-8d2e-00505689a76b, postOffice=PostOfficeImpl [server=ActiveMQServerImpl::serverUUID=2f00c36f-2034-11ec-8d2e-00505689a76b], temp=true]@4180826b, filter=null, name=d1586796-2035-11ec-8d2e-00505689a76b, clusterName=d1586796-2035-11ec-8d2e-00505689a76b2f00c36f-2034-11ec-8d2e-00505689a76b]], message=Reference[2019]:RELIABLE:CoreMessage[messageID=2019,durable=true,userID=d5e2d1c3-2035-11ec-8d2e-00505689a76b,priority=4, timestamp=Tue Sep 28 10:26:53 CEST 2021,expiration=0, durable=true, address=jms.topic.defended_assetFull,size=6520,properties=TypedProperties[__AMQ_CID=f9eab79a-2034-11ec-8d2e-00505689a76b,_AMQ_ROUTING_TYPE=0]]@155890432: java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909)
at java.util.ArrayList$Itr.next(ArrayList.java:859)
at org.apache.activemq.artemis.core.server.impl.RefsOperation.afterCommit(RefsOperation.java:179)
at org.apache.activemq.artemis.core.transaction.impl.TransactionImpl.afterCommit(TransactionImpl.java:579)
at org.apache.activemq.artemis.core.transaction.impl.TransactionImpl.access$100(TransactionImpl.java:40)
at org.apache.activemq.artemis.core.transaction.impl.TransactionImpl$2.done(TransactionImpl.java:322)
at org.apache.activemq.artemis.core.persistence.impl.journal.OperationContextImpl.executeOnCompletion(OperationContextImpl.java:190)
at org.apache.activemq.artemis.core.persistence.impl.journal.OperationContextImpl.executeOnCompletion(OperationContextImpl.java:128)
at org.apache.activemq.artemis.core.persistence.impl.journal.AbstractJournalStorageManager.afterCompleteOperations(AbstractJournalStorageManager.java:321)
at org.apache.activemq.artemis.core.transaction.impl.TransactionImpl.commit(TransactionImpl.java:313)
at org.apache.activemq.artemis.core.transaction.impl.TransactionImpl.commit(TransactionImpl.java:264)
at org.apache.activemq.artemis.core.server.impl.ServerSessionImpl.commit(ServerSessionImpl.java:1284)
at org.apache.activemq.artemis.core.protocol.stomp.StompSession$1.run(StompSession.java:164)
at org.apache.activemq.artemis.core.protocol.stomp.StompSession.afterDelivery(StompSession.java:116)
at org.apache.activemq.artemis.core.server.impl.ServerConsumerImpl.proceedDeliver(ServerConsumerImpl.java:511)
at org.apache.activemq.artemis.core.server.impl.QueueImpl.proceedDeliver(QueueImpl.java:3744)
at org.apache.activemq.artemis.core.server.impl.QueueImpl.deliver(QueueImpl.java:3048)
at org.apache.activemq.artemis.core.server.impl.QueueImpl.access$2400(QueueImpl.java:125)
at org.apache.activemq.artemis.core.server.impl.QueueImpl$DeliverRunner.run(QueueImpl.java:4119)
at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:42)
at org.apache.activemq.artemis.utils.actors.OrderedExecutor.doTask(OrderedExecutor.java:31)
at org.apache.activemq.artemis.utils.actors.ProcessorBase.executePendingTasks(ProcessorBase.java:65)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.activemq.artemis.utils.ActiveMQThreadFactory$1.run(ActiveMQThreadFactory.java:118)

Clients are connected to stomp acceptor:

<acceptor name="stomp-over-ws" factory-class="org.apache.activemq.artemis.core.remoting.impl.netty.NettyAcceptorFactory">
<param name="host" value="0.0.0.0" />
<param name="protocols" value="STOMP" />
<param name="port" value="61614" />
</acceptor>