org.xwiki.rendering.macro.MacroExecutionException: Failed to evaluate Velocity Macro for content [{{html clean="false"}}
## In case the current page has an ImageClass object
## declare it as the first og:image in the list
#set ($image = $doc.getObject('XWiki.Image.ImageClass'))
#set ($hasFeaturedImage = false)
#if ($image != $NULL && "$!image.getValue('reference')" != '')
  #set ($hasFeaturedImage = true)
  #set ($ref = $image.getValue('reference'))
  <meta property="og:image" content="$doc.getDocument().getExternalAttachmentURL($ref, 'download', $xcontext.context)" />
#end
#foreach ($property in $services.opengraph.metas().entrySet())
  #foreach ($content in $property.value)
    #if ($property.key != 'og:image' || !$hasFeaturedImage)
      <meta property="$escapetool.xml($property.key)" content="$escapetool.xml($content)" />
    #end
  #end
#end
{{/html}}]
 at org.xwiki.rendering.internal.macro.velocity.VelocityMacro.evaluateString(VelocityMacro.java:135)
 at org.xwiki.rendering.internal.macro.velocity.VelocityMacro.evaluateString(VelocityMacro.java:51)
 at org.xwiki.rendering.macro.script.AbstractScriptMacro.evaluateBlock(AbstractScriptMacro.java:279)
 at org.xwiki.rendering.macro.script.AbstractScriptMacro.execute(AbstractScriptMacro.java:182)
 at org.xwiki.rendering.macro.script.AbstractScriptMacro.execute(AbstractScriptMacro.java:58)
 at org.xwiki.rendering.internal.transformation.macro.MacroTransformation.transform(MacroTransformation.java:309)
 at org.xwiki.rendering.internal.transformation.DefaultRenderingContext.transformInContext(DefaultRenderingContext.java:183)
 at org.xwiki.rendering.async.internal.block.AbstractBlockAsyncRenderer.transform(AbstractBlockAsyncRenderer.java:76)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRenderer.tranform(DefaultBlockAsyncRenderer.java:154)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRenderer.execute(DefaultBlockAsyncRenderer.java:137)
 at org.xwiki.rendering.async.internal.block.AbstractBlockAsyncRenderer.render(AbstractBlockAsyncRenderer.java:157)
 at org.xwiki.uiextension.internal.WikiUIExtension.render(WikiUIExtension.java:200)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor$DecoratorWrapper.render(DefaultBlockAsyncRendererExecutor.java:67)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor$DecoratorWrapper.render(DefaultBlockAsyncRendererExecutor.java:49)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.lambda$syncRender$0(DefaultAsyncRendererExecutor.java:284)
 at com.xpn.xwiki.internal.security.authorization.DefaultAuthorExecutor.call(DefaultAuthorExecutor.java:98)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.syncRender(DefaultAsyncRendererExecutor.java:284)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.render(DefaultAsyncRendererExecutor.java:267)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor.execute(DefaultBlockAsyncRendererExecutor.java:125)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor.execute(DefaultBlockAsyncRendererExecutor.java:113)
 at org.xwiki.uiextension.internal.AbstractWikiUIExtension.execute(AbstractWikiUIExtension.java:120)
 at org.xwiki.uiextension.internal.AbstractWikiUIExtension.execute(AbstractWikiUIExtension.java:108)
 at jdk.internal.reflect.GeneratedMethodAccessor250.invoke(Unknown Source)
 at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.base/java.lang.reflect.Method.invoke(Method.java:566)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.doInvoke(UberspectImpl.java:571)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:554)
 at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:221)
 at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:368)
 at org.apache.velocity.runtime.parser.node.ASTReference.value(ASTReference.java:704)
 at org.apache.velocity.runtime.parser.node.ASTExpression.value(ASTExpression.java:75)
 at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:167)
 at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:368)
 at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:492)
 at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:147)
 at org.apache.velocity.runtime.directive.Foreach.renderBlock(Foreach.java:309)
 at org.apache.velocity.runtime.directive.Foreach.render(Foreach.java:279)
 at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:304)
 at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:439)
 at org.apache.velocity.runtime.directive.Evaluate.render(Evaluate.java:213)
 at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:304)
 at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:147)
 at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:171)
 at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:439)
 at org.apache.velocity.Template.merge(Template.java:358)
 at org.apache.velocity.Template.merge(Template.java:262)
 at org.xwiki.velocity.internal.DefaultVelocityEngine.evaluate(DefaultVelocityEngine.java:280)
 at com.xpn.xwiki.render.DefaultVelocityManager.evaluate(DefaultVelocityManager.java:321)
 at com.xpn.xwiki.internal.template.VelocityTemplateEvaluator.evaluateContent(VelocityTemplateEvaluator.java:95)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.evaluateContent(TemplateAsyncRenderer.java:222)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.renderVelocity(TemplateAsyncRenderer.java:177)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:138)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:54)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.lambda$syncRender$0(DefaultAsyncRendererExecutor.java:284)
 at com.xpn.xwiki.internal.security.authorization.DefaultAuthorExecutor.call(DefaultAuthorExecutor.java:98)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.syncRender(DefaultAsyncRendererExecutor.java:284)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.render(DefaultAsyncRendererExecutor.java:267)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor.render(DefaultBlockAsyncRendererExecutor.java:154)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:843)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:805)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:785)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:771)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:91)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:85)
 at com.xpn.xwiki.XWiki.evaluateTemplate(XWiki.java:2553)
 at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:2531)
 at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:1000)
 at jdk.internal.reflect.GeneratedMethodAccessor224.invoke(Unknown Source)
 at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.base/java.lang.reflect.Method.invoke(Method.java:566)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.doInvoke(UberspectImpl.java:571)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:554)
 at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:221)
 at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:368)
 at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:492)
 at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:147)
 at org.apache.velocity.runtime.directive.VelocimacroProxy.render(VelocimacroProxy.java:218)
 at org.apache.velocity.runtime.directive.RuntimeMacro.render(RuntimeMacro.java:331)
 at org.apache.velocity.runtime.directive.RuntimeMacro.render(RuntimeMacro.java:261)
 at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:304)
 at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:439)
 at org.apache.velocity.Template.merge(Template.java:358)
 at org.apache.velocity.Template.merge(Template.java:262)
 at org.xwiki.velocity.internal.DefaultVelocityEngine.evaluate(DefaultVelocityEngine.java:280)
 at com.xpn.xwiki.render.DefaultVelocityManager.evaluate(DefaultVelocityManager.java:321)
 at com.xpn.xwiki.internal.template.VelocityTemplateEvaluator.evaluateContent(VelocityTemplateEvaluator.java:95)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.evaluateContent(TemplateAsyncRenderer.java:222)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.renderVelocity(TemplateAsyncRenderer.java:177)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:138)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:54)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.lambda$syncRender$0(DefaultAsyncRendererExecutor.java:284)
 at com.xpn.xwiki.internal.security.authorization.DefaultAuthorExecutor.call(DefaultAuthorExecutor.java:98)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.syncRender(DefaultAsyncRendererExecutor.java:284)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.render(DefaultAsyncRendererExecutor.java:267)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor.render(DefaultBlockAsyncRendererExecutor.java:154)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:843)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:805)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:785)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:771)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:91)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:85)
 at com.xpn.xwiki.XWiki.evaluateTemplate(XWiki.java:2553)
 at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:2531)
 at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:1000)
 at jdk.internal.reflect.GeneratedMethodAccessor224.invoke(Unknown Source)
 at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.base/java.lang.reflect.Method.invoke(Method.java:566)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.doInvoke(UberspectImpl.java:571)
 at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:554)
 at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:221)
 at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:368)
 at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:492)
 at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:147)
 at org.apache.velocity.runtime.directive.VelocimacroProxy.render(VelocimacroProxy.java:218)
 at org.apache.velocity.runtime.directive.RuntimeMacro.render(RuntimeMacro.java:331)
 at org.apache.velocity.runtime.directive.RuntimeMacro.render(RuntimeMacro.java:261)
 at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:304)
 at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:439)
 at org.apache.velocity.Template.merge(Template.java:358)
 at org.apache.velocity.Template.merge(Template.java:262)
 at org.xwiki.velocity.internal.DefaultVelocityEngine.evaluate(DefaultVelocityEngine.java:280)
 at com.xpn.xwiki.render.DefaultVelocityManager.evaluate(DefaultVelocityManager.java:321)
 at com.xpn.xwiki.internal.template.VelocityTemplateEvaluator.evaluateContent(VelocityTemplateEvaluator.java:95)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.evaluateContent(TemplateAsyncRenderer.java:222)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.renderVelocity(TemplateAsyncRenderer.java:177)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:138)
 at com.xpn.xwiki.internal.template.TemplateAsyncRenderer.render(TemplateAsyncRenderer.java:54)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.lambda$syncRender$0(DefaultAsyncRendererExecutor.java:284)
 at com.xpn.xwiki.internal.security.authorization.DefaultAuthorExecutor.call(DefaultAuthorExecutor.java:98)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.syncRender(DefaultAsyncRendererExecutor.java:284)
 at org.xwiki.rendering.async.internal.DefaultAsyncRendererExecutor.render(DefaultAsyncRendererExecutor.java:267)
 at org.xwiki.rendering.async.internal.block.DefaultBlockAsyncRendererExecutor.render(DefaultBlockAsyncRendererExecutor.java:154)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:843)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:805)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.renderFromSkin(InternalTemplateManager.java:785)
 at com.xpn.xwiki.internal.template.InternalTemplateManager.render(InternalTemplateManager.java:771)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:91)
 at com.xpn.xwiki.internal.template.DefaultTemplateManager.render(DefaultTemplateManager.java:85)
 at com.xpn.xwiki.XWiki.evaluateTemplate(XWiki.java:2553)
 at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:180)
 at org.xwiki.security.authentication.internal.resource.AuthenticationResourceReferenceHandler.handleAction(AuthenticationResourceReferenceHandler.java:122)
 at org.xwiki.security.authentication.internal.resource.AuthenticationResourceReferenceHandler.handle(AuthenticationResourceReferenceHandler.java:96)
 at org.xwiki.resource.internal.DefaultResourceReferenceHandlerChain.handleNext(DefaultResourceReferenceHandlerChain.java:79)
 at org.xwiki.resource.internal.AbstractResourceReferenceHandlerManager.handle(AbstractResourceReferenceHandlerManager.java:82)
 at org.xwiki.resource.servlet.ResourceReferenceHandlerServlet.handleResourceReference(ResourceReferenceHandlerServlet.java:159)
 at org.xwiki.resource.servlet.ResourceReferenceHandlerServlet.service(ResourceReferenceHandlerServlet.java:87)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:733)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
 at org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
 at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:710)
 at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:457)
 at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:352)
 at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:312)
 at org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:145)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:143)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
 at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:764)
 at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:687)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:354)
 at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382)
 at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
 at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:888)
 at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1684)
 at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
 at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
 at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
 at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: org.xwiki.velocity.XWikiVelocityException: Failed to evaluate content with namespace [xwiki:XWiki.OpenGraphUIX^XWiki.UIExtensionClass[0]]
 at org.xwiki.velocity.internal.DefaultVelocityEngine.evaluate(DefaultVelocityEngine.java:289)
 at com.xpn.xwiki.render.DefaultVelocityManager.evaluate(DefaultVelocityManager.java:321)
 at org.xwiki.rendering.internal.macro.velocity.VelocityMacro.evaluateString(VelocityMacro.java:127)
 ... 176 more
Caused by: org.apache.velocity.exception.MethodInvocationException: Invocation of method 'metas' in  class org.xwiki.contrib.opengraph.script.OpenGraphScriptService threw exception java.lang.NullPointerException at xwiki:XWiki.OpenGraphUIX^XWiki.UIExtensionClass[0][line 11, column 44]
 at org.apache.velocity.runtime.parser.node.ASTMethod.handleInvocationException(ASTMethod.java:308)
 at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:235)
 at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:368)
 at org.apache.velocity.runtime.parser.node.ASTReference.value(ASTReference.java:704)
 at org.apache.velocity.runtime.directive.Foreach.render(Foreach.java:237)
 at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:304)
 at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:439)
 at org.apache.velocity.Template.merge(Template.java:358)
 at org.apache.velocity.Template.merge(Template.java:262)
 at org.xwiki.velocity.internal.DefaultVelocityEngine.evaluate(DefaultVelocityEngine.java:280)
 ... 178 more
Caused by: java.lang.NullPointerException