Error loading Smarter User Picker module

[Brennon Bortz]

Smarter User Picker is suddenly consistently failing to load for us, and logging this error;

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'smartUserPickerService' defined in URL [bundle://118.0:0/META-INF/spring/atlassian-plugins-components.xml]: Invocation of init method failed; nested exception is java.lang.ClassCastException: com.atlassian.jira.user.DelegatingApplicationUser cannot be cast to com.atlassian.crowd.embedded.api.User
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
 at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
 at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
 at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
 at org.eclipse.gemini.blueprint.context.support.AbstractDelegatedExecutionApplicationContext.access$1600(AbstractDelegatedExecutionApplicationContext.java:60)
 at org.eclipse.gemini.blueprint.context.support.AbstractDelegatedExecutionApplicationContext$4.run(AbstractDelegatedExecutionApplicationContext.java:325)
 at org.eclipse.gemini.blueprint.util.internal.PrivilegedUtils.executeWithCustomTCCL(PrivilegedUtils.java:85)
 at org.eclipse.gemini.blueprint.context.support.AbstractDelegatedExecutionApplicationContext.completeRefresh(AbstractDelegatedExecutionApplicationContext.java:290)
 at org.eclipse.gemini.blueprint.extender.internal.dependencies.startup.DependencyWaiterApplicationContextExecutor$CompleteRefreshTask.run(DependencyWaiterApplicationContextExecutor.java:137)
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
 at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassCastException: com.atlassian.jira.user.DelegatingApplicationUser cannot be cast to com.atlassian.crowd.embedded.api.User
 at com.atlassian.labs.smarteruserpicker.SmarterUserPickerSearchServiceImpl.buildIndex(SmarterUserPickerSearchServiceImpl.java:212)
 at com.atlassian.labs.smarteruserpicker.SmarterUserPickerSearchServiceImpl.afterPropertiesSet(SmarterUserPickerSearchServiceImpl.java:99)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1633)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1570)
 ... 16 more

The plugin will later enable for us, but then we get an exception similar to this is logged on nearly every page load (literally gigs of logs every hour or so):

2018-11-06 10:04:39,164 http-nio-8080-exec-21 ERROR <username redacted> 604x97681x1 xquspp <IP address redacted> /secure/RapidBoard.jspa [c.a.templaterenderer.plugins.TemplateContextFactoryImpl] Error loading module for com.atlassian.labs.smarter-user-picker-plugin:applicationPropertiesContextItem
java.lang.NullPointerException
 at com.atlassian.templaterenderer.plugins.TemplateContextItemModuleDescriptor.getApplicationContext(TemplateContextItemModuleDescriptor.java:101)
 at com.atlassian.templaterenderer.plugins.TemplateContextItemModuleDescriptor.getModule(TemplateContextItemModuleDescriptor.java:77)
 at com.atlassian.templaterenderer.plugins.TemplateContextFactoryImpl.createContext(TemplateContextFactoryImpl.java:47)
 at sun.reflect.GeneratedMethodAccessor381.invoke(Unknown Source)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.lang.reflect.Method.invoke(Method.java:498)
 at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
 at org.eclipse.gemini.blueprint.service.importer.support.internal.aop.ServiceInvoker.doInvoke(ServiceInvoker.java:56)
 at org.eclipse.gemini.blueprint.service.importer.support.internal.aop.ServiceInvoker.invoke(ServiceInvoker.java:60)
 at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
 at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:133)
 at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:121)
 at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
 at org.eclipse.gemini.blueprint.service.util.internal.aop.ServiceTCCLInterceptor.invokeUnprivileged(ServiceTCCLInterceptor.java:70)
 at org.eclipse.gemini.blueprint.service.util.internal.aop.ServiceTCCLInterceptor.invoke(ServiceTCCLInterceptor.java:53)
 at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
 at org.eclipse.gemini.blueprint.service.importer.support.LocalBundleContextAdvice.invoke(LocalBundleContextAdvice.java:57)
 at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
 at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:133)
 at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:121)
 at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
 at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
 at com.sun.proxy.$Proxy837.createContext(Unknown Source)
 at com.atlassian.templaterenderer.velocity.one.six.internal.VelocityTemplateRendererImpl.createContext(VelocityTemplateRendererImpl.java:134)
 at com.atlassian.templaterenderer.velocity.one.six.internal.VelocityTemplateRendererImpl.render(VelocityTemplateRendererImpl.java:100)
 at com.atlassian.templaterenderer.velocity.AbstractCachingWebPanelRenderer.render(AbstractCachingWebPanelRenderer.java:53)
 at com.atlassian.plugin.web.model.ResourceTemplateWebPanel.writeHtml(ResourceTemplateWebPanel.java:50)
 at com.atlassian.plugin.web.model.ResourceTemplateWebPanel.getHtml(ResourceTemplateWebPanel.java:65)
 at com.atlassian.plugin.web.descriptors.DefaultWebPanelModuleDescriptor$ContextAwareWebPanel.getHtml(DefaultWebPanelModuleDescriptor.java:144)
 at com.atlassian.jira.plugin.headernav.ModernPluggableTopNavigation.getHtml(ModernPluggableTopNavigation.java:56)
 at com.atlassian.jira.plugin.navigation.HeaderFooterRendering$7.visit(HeaderFooterRendering.java:334)
 at com.atlassian.jira.plugin.navigation.HeaderFooterRendering$7.visit(HeaderFooterRendering.java:326)
 at com.atlassian.ozymandias.SafePluginPointAccess.invokeModule(SafePluginPointAccess.java:452)
 at com.atlassian.ozymandias.SafePluginPointAccess.descriptors(SafePluginPointAccess.java:150)
 at com.atlassian.jira.plugin.navigation.HeaderFooterRendering.includeTopNavigation(HeaderFooterRendering.java:326)
 at com.atlassian.jira.plugin.navigation.HeaderFooterRendering$1.run(HeaderFooterRendering.java:142)
 at com.atlassian.ozymandias.SafePluginPointAccess.runnable(SafePluginPointAccess.java:201)
 at com.atlassian.jira.plugin.navigation.HeaderFooterRendering.includeTopNavigation(HeaderFooterRendering.java:139)
 at jsp.decorators.general_jsp._jspService(general_jsp.java:279)
 at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
 ... 51 filtered
 at com.atlassian.jira.security.JiraSecurityFilter.doFilter(JiraSecurityFilter.java:70)
 ... 93 filtered
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
 at java.lang.Thread.run(Thread.java:745)

I can't find anything about this issue, and for that matter, can't find where to appropriately report the issue. Any help would be appreciated.