Logging in into CMS when there is a document open (in draft) for current user results in server error

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[INFO] [talledLocalContainer] 04.09.2018 16:01:00 ERROR http-nio-8080-exec-5 [DefaultExceptionMapper.mapUnexpectedExceptions:170] Unexpected error occurred
[INFO] [talledLocalContainer] org.apache.wicket.WicketRuntimeException: Can't instantiate page using constructor 'public org.hippoecm.frontend.PluginPage()'. An exception has been thrown during construction!
[INFO] [talledLocalContainer] at org.apache.wicket.session.DefaultPageFactory.newPage(DefaultPageFactory.java:194) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.session.DefaultPageFactory.newPage(DefaultPageFactory.java:67) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.DefaultMapperContext.newPageInstance(DefaultMapperContext.java:133) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.core.request.handler.PageProvider.resolvePageInstance(PageProvider.java:268) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.core.request.handler.PageProvider.getPageInstance(PageProvider.java:166) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.handler.render.PageRenderer.getPage(PageRenderer.java:78) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.handler.render.WebPageRenderer.respond(WebPageRenderer.java:279) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.core.request.handler.RenderPageRequestHandler.respond(RenderPageRequestHandler.java:175) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:890) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64) ~[wicket-request-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:261) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:218) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:289) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.processRequestCycle(WicketFilter.java:259) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:201) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:282) [wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.login.ConcurrentLoginFilter.doFilter(ConcurrentLoginFilter.java:54) [hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [catalina.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-coyote.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-coyote.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) [tomcat-coyote.jar:8.5.31]
[INFO] [talledLocalContainer] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:8.5.31]
[INFO] [talledLocalContainer] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_144]
[INFO] [talledLocalContainer] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_144]
[INFO] [talledLocalContainer] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.5.31]
[INFO] [talledLocalContainer] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]
[INFO] [talledLocalContainer] Caused by: java.lang.reflect.InvocationTargetException
[INFO] [talledLocalContainer] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at org.apache.wicket.session.DefaultPageFactory.newPage(DefaultPageFactory.java:175) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] ... 37 more
[INFO] [talledLocalContainer] Caused by: java.lang.IllegalStateException: BranchIdModel is undefined, please make sure to initialize the branchIdModel before creating the editor
[INFO] [talledLocalContainer] at org.hippoecm.frontend.editor.HippostdPublishableEditor.<init>(HippostdPublishableEditor.java:183) ~[hippo-cms-workflow-frontend-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.reviewedactions.HippostdEditorFactoryPlugin.newEditor(HippostdEditorFactoryPlugin.java:69) ~[hippo-cms-workflow-frontend-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.reviewedactions.HippostdEditorFactoryPlugin.newEditor(HippostdEditorFactoryPlugin.java:44) ~[hippo-cms-workflow-frontend-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.cms.edit.EditorManagerPlugin$1.newEditor(EditorManagerPlugin.java:101) ~[hippo-cms-perspectives-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.cms.edit.EditorManagerPlugin.createEditor(EditorManagerPlugin.java:171) ~[hippo-cms-perspectives-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.cms.edit.EditorManagerPlugin.openEditor(EditorManagerPlugin.java:147) ~[hippo-cms-perspectives-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugins.cms.edit.AutoEditPlugin.start(AutoEditPlugin.java:74) ~[hippo-cms-perspectives-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugin.impl.PluginContext.connect(PluginContext.java:339) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugin.impl.PluginManager.start(PluginManager.java:86) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugin.impl.PluginContext.start(PluginContext.java:372) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.plugin.impl.ClusterControl.start(ClusterControl.java:125) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.PluginPage.<init>(PluginPage.java:110) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at org.hippoecm.frontend.PluginPage.<init>(PluginPage.java:72) ~[hippo-cms-engine-5.6.0-campaigns-psp1-SNAPSHOT.jar:5.6.0-campaigns-psp1-SNAPSHOT]
[INFO] [talledLocalContainer] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_144]
[INFO] [talledLocalContainer] at org.apache.wicket.session.DefaultPageFactory.newPage(DefaultPageFactory.java:175) ~[wicket-core-6.29.0.jar:6.29.0]
[INFO] [talledLocalContainer] ... 37 more