java.lang.IllegalStateException: Duplicate key 0 seen in logs

This content is relevant under the following criteria:

You have installed Excellentable v4.2.3 or higher on Confluence Data Center
You previously installed Excellentable v4.2.1

Issue:

The following log message is seen on the backend. This is caused from an identified issue when installing the Excellentable v4.2.1 release which caused duplicate entries to be added to the What's New DB table. This issue causes the marketing popups (shown below) to not be shown to any of the users. This does not have any affect on any of your Excellentables.

CODE

2020-10-05 11:21:25,506 DEBUG [http-nio-8090-exec-8] [plugin.excellentable.rest.ExcellentableRest] isEvaluationLicense Is AnalyticsEnabled from cache is true
2020-10-05 11:21:25,627 WARN [http-nio-8090-exec-4] [confluence.impl.hibernate.ConfluenceHibernateTransactionManager] doRollback Performing rollback. Transactions:
  ->[PluginReadWriteTx]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT (Session #1139191666)
 -- referer: https://confluence-dc2.addteq.com/pages/viewpage.action?pageId=3932465 | url: /rest/excellentable/1.0/whatsnew/view | traceId: ed7f78b72c865fd4 | userName: ghostadmin1
2020-10-05 11:21:25,629 ERROR [http-nio-8090-exec-4] [rest.api.model.ExceptionConverter] convertServiceException No status code found for exception, converting to internal server error : 
 -- referer: https://confluence-dc2.addteq.com/pages/viewpage.action?pageId=3932465 | url: /rest/excellentable/1.0/whatsnew/view | traceId: ed7f78b72c865fd4 | userName: ghostadmin1
java.lang.IllegalStateException: Duplicate key 0 (attempted merging values [Ljava.lang.String;@e6c5a3a and [Ljava.lang.String;@6eb0ec22)
        at java.base/java.util.stream.Collectors.duplicateKeyException(Unknown Source)
        at java.base/java.util.stream.Collectors.lambda$uniqKeysMapAccumulator$1(Unknown Source)
        at java.base/java.util.stream.ReduceOps$3ReducingSink.accept(Unknown Source)
        at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(Unknown Source)
        at java.base/java.util.stream.AbstractPipeline.copyInto(Unknown Source)
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source)
        at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(Unknown Source)
        at java.base/java.util.stream.AbstractPipeline.evaluate(Unknown Source)
        at java.base/java.util.stream.ReferencePipeline.collect(Unknown Source)
        at com.addteq.confluence.plugin.excellentable.whatsNew.model.WhatsNewModel.setData(WhatsNewModel.java:56)
        at com.addteq.confluence.plugin.excellentable.whatsNew.service.WhatsNewServiceImpl.lambda$getData$1(WhatsNewServiceImpl.java:46)
        at com.atlassian.sal.core.transaction.HostContextTransactionTemplate$1.doInTransaction(HostContextTransactionTemplate.java:21)
        at com.atlassian.sal.spring.component.SpringHostContextAccessor.lambda$doInTransaction$0(SpringHostContextAccessor.java:70)
        at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140)
        at com.atlassian.sal.spring.component.SpringHostContextAccessor.doInTransaction(SpringHostContextAccessor.java:68)
        at com.atlassian.confluence.spring.transaction.interceptor.ConfluenceSpringHostContextAccessor.access$001(ConfluenceSpringHostContextAccessor.java:21)
        at com.atlassian.confluence.spring.transaction.interceptor.ConfluenceSpringHostContextAccessor.lambda$doInTransaction$3(ConfluenceSpringHostContextAccessor.java:72)
        at com.atlassian.confluence.impl.vcache.VCacheRequestContextManager.doInRequestContextInternal(VCacheRequestContextManager.java:84)
        at com.atlassian.confluence.impl.vcache.VCacheRequestContextManager.doInRequestContext(VCacheRequestContextManager.java:68)
        at com.atlassian.confluence.spring.transaction.interceptor.ConfluenceSpringHostContextAccessor.doInTransaction(ConfluenceSpringHostContextAccessor.java:72)
        at com.atlassian.sal.core.transaction.HostContextTransactionTemplate.execute(HostContextTransactionTemplate.java:18)
        at jdk.internal.reflect.GeneratedMethodAccessor271.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.base/java.lang.reflect.Method.invoke(Unknown Source)
        at com.atlassian.plugin.util.ContextClassLoaderSettingInvocationHandler.invoke(ContextClassLoaderSettingInvocationHandler.java:26)
        at com.sun.proxy.$Proxy208.execute(Unknown Source)
        at jdk.internal.reflect.GeneratedMethodAccessor271.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

A fix for this issue will be present in a future release