I experimented with a new build of 1.12 and copied over flow.xml.gz from an older NiFi (1.8 and 1.11) and now get this. Did something change? Because I have a version of 1.12 that I built a few weeks ago where I'm not getting this with the same flow.xml.gz
org.apache.nifi.controller.serialization.FlowSynchronizationException: java.lang.IllegalStateException: The specified class 'org.apache.nifi.prioritizer.FirstInFirstOutPrioritizer' is not known to this nifi. at org.apache.nifi.controller.StandardFlowSynchronizer.sync(StandardFlowSynchronizer.java:306) at org.apache.nifi.controller.FlowController.synchronize(FlowController.java:1425) at org.apache.nifi.persistence.StandardXMLFlowConfigurationDAO.load(StandardXMLFlowConfigurationDAO.java:89) at org.apache.nifi.controller.StandardFlowService.loadFromBytes(StandardFlowService.java:792) at org.apache.nifi.controller.StandardFlowService.load(StandardFlowService.java:537) at org.apache.nifi.web.contextlistener.ApplicationStartupContextListener.contextInitialized(ApplicationStartupContextListener.java:72) at org.eclipse.jetty.server.handler.ContextHandler.callContextInitialized(ContextHandler.java:930) at org.eclipse.jetty.servlet.ServletContextHandler.callContextInitialized(ServletContextHandler.java:553) at org.eclipse.jetty.server.handler.ContextHandler.startContext(ContextHandler.java:889) at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:356) at org.eclipse.jetty.webapp.WebAppContext.startWebapp(WebAppContext.java:1445) at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1409) at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:822) at org.eclipse.jetty.servlet.ServletContextHandler.doStart(ServletContextHandler.java:275) at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:524) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:117) at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:97) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110) at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:97) at org.eclipse.jetty.server.handler.gzip.GzipHandler.doStart(GzipHandler.java:425) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:117) at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:97) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:117) at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:97) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) at org.eclipse.jetty.server.Server.start(Server.java:407) at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110) at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:97) at org.eclipse.jetty.server.Server.doStart(Server.java:371) at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) at org.apache.nifi.web.server.JettyServer.start(JettyServer.java:1060) at org.apache.nifi.NiFi.<init>(NiFi.java:160) at org.apache.nifi.NiFi.<init>(NiFi.java:72) at org.apache.nifi.NiFi.main(NiFi.java:303) Caused by: java.lang.IllegalStateException: The specified class 'org.apache.nifi.prioritizer.FirstInFirstOutPrioritizer' is not known to this nifi. at org.apache.nifi.controller.flow.StandardFlowManager.createPrioritizer(StandardFlowManager.java:309) at org.apache.nifi.controller.StandardFlowSynchronizer.addConnections(StandardFlowSynchronizer.java:1667) at org.apache.nifi.controller.StandardFlowSynchronizer.addProcessGroup(StandardFlowSynchronizer.java:1324) at org.apache.nifi.controller.StandardFlowSynchronizer.addNestedProcessGroups(StandardFlowSynchronizer.java:1333) at org.apache.nifi.controller.StandardFlowSynchronizer.addProcessGroup(StandardFlowSynchronizer.java:1322) at org.apache.nifi.controller.StandardFlowSynchronizer.addNestedProcessGroups(StandardFlowSynchronizer.java:1333) at org.apache.nifi.controller.StandardFlowSynchronizer.addProcessGroup(StandardFlowSynchronizer.java:1322) at org.apache.nifi.controller.StandardFlowSynchronizer.updateFlow(StandardFlowSynchronizer.java:432) at org.apache.nifi.controller.StandardFlowSynchronizer.sync(StandardFlowSynchronizer.java:283) ... 42 common frames omitted