[Backport to 13.0] Error Perhaps the behavior did not properly implement getStatelessHint() and returned 'true' to indicate that it is stateless instead of returning 'false'

[INFO] [talledLocalContainer] 01.03.2019 13:55:01 ERROR http-nio-8080-exec-7 [DefaultExceptionMapper.mapUnexpectedExceptions:170] Unexpected error occurred[INFO] [talledLocalContainer] 01.03.2019 13:55:01 ERROR http-nio-8080-exec-7 [DefaultExceptionMapper.mapUnexpectedExceptions:170] Unexpected error occurred[INFO] [talledLocalContainer]  org.apache.wicket.behavior.InvalidBehaviorIdException: Cannot find behavior with id '0' on component 'org.apache.wicket.markup.html.basic.Label:root:pinger' in page '[Page class = org.hippoecm.frontend.PluginPage, id = 0, render count = 0]'. Perhaps the behavior did not properly implement getStatelessHint() and returned 'true' to indicate that it is stateless instead of returning 'false' to indicate that it is stateful.[INFO] [talledLocalContainer] at org.apache.wicket.Behaviors.getBehaviorById(Behaviors.java:316) ~[wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.Component.getBehaviorById(Component.java:4598) ~[wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.invokeListener(ListenerInterfaceRequestHandler.java:247) ~[wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.respond(ListenerInterfaceRequestHandler.java:234) ~[wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:895) ~[wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64) ~[wicket-request-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:265) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:222) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:293) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.processRequestCycle(WicketFilter.java:261) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:203) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:284) [wicket-core-7.11.0.jar:7.11.0][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.login.ConcurrentLoginFilter.doFilter(ConcurrentLoginFilter.java:54) [hippo-cms-login-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.FilterChainInvokingValve.invoke(FilterChainInvokingValve.java:72) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.JCRSessionStatefulConcurrencyValve.invoke(JCRSessionStatefulConcurrencyValve.java:56) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.SubjectBasedSessionValve.invoke(SubjectBasedSessionValve.java:58) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.SecurityValve.invoke(SecurityValve.java:177) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.LocalizationValve.invoke(LocalizationValve.java:101) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.CmsSecurityValve.invoke(CmsSecurityValve.java:59) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.InitializationValve.invoke(InitializationValve.java:37) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline$Invocation.invokeNext(HstSitePipeline.java:288) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline.invokeValves(HstSitePipeline.java:173) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstSitePipeline.invoke(HstSitePipeline.java:155) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.core.container.HstRequestProcessorImpl.processRequest(HstRequestProcessorImpl.java:79) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.container.HstDelegateeFilterBean.doFilter(HstDelegateeFilterBean.java:462) [hst-core-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.container.DelegatingFilter.doFilter(DelegatingFilter.java:68) [hst-commons-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.hippoecm.hst.container.HstFilter.doFilter(HstFilter.java:51) [hst-commons-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.onehippo.cms7.utilities.servlet.ProxyFilter.doFilter(ProxyFilter.java:125) [hippo-cms7-utilities-13.1.0-SNAPSHOT.jar:13.1.0-SNAPSHOT][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [catalina.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) [tomcat-coyote.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:791) [tomcat-coyote.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417) [tomcat-coyote.jar:9.0.13][INFO] [talledLocalContainer] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:9.0.13][INFO] [talledLocalContainer] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_201][INFO] [talledLocalContainer] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_201][INFO] [talledLocalContainer] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:9.0.13][INFO] [talledLocalContainer] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_201]