Emoji characters break Office export

com.sun.org.apache.bcel.internal.generic.ClassGenException: Assigning null to handle
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionHandle.setInstruction(InstructionHandle.java:90)
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionHandle.<init>(InstructionHandle.java:121)
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionHandle.getInstructionHandle(InstructionHandle.java:127)
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionList.append(InstructionList.java:321)
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionList.<init>(InstructionList.java:72)
        at java.xml/com.sun.org.apache.bcel.internal.generic.InstructionList.insert(InstructionList.java:557)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.Mode.peepHoleOptimization(Mode.java:1440)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.Mode.compileApplyTemplates(Mode.java:1018)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.Stylesheet.compileModes(Stylesheet.java:622)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.Stylesheet.translate(Stylesheet.java:735)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.XSLTC.compile(XSLTC.java:503)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.compiler.XSLTC.compile(XSLTC.java:570)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:1018)
        at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTransformer(TransformerFactoryImpl.java:817)
        at org.xwiki.xml.XMLUtils.transform(XMLUtils.java:431)
        at com.xpn.xwiki.pdf.impl.PdfExportImpl.applyXSLT(PdfExportImpl.java:281)
        at com.xpn.xwiki.internal.export.OfficeExporter.exportXHTML(OfficeExporter.java:99)
        at com.xpn.xwiki.internal.export.OfficeExporter.exportXHTML(OfficeExporter.java:82)
        at com.xpn.xwiki.pdf.impl.PdfExportImpl.exportHtml(PdfExportImpl.java:173)
        at com.xpn.xwiki.pdf.impl.PdfExportImpl.export(PdfExportImpl.java:159)
        at com.xpn.xwiki.web.ExportAction.export(ExportAction.java:184)
        at com.xpn.xwiki.web.ExportAction.render(ExportAction.java:91)
        at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:560)
        at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:250)
        at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
        at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
        at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
        at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:112)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.wysiwyg.filter.ConversionFilter.doFilter(ConversionFilter.java:109)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:132)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:688)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1639)
        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:834)
ERROR:  'Could not compile stylesheet'
FATAL ERROR:  'Assigning null to handle'
           :Assigning null to handle
2020-03-27 16:47:38,680 [http://localhost:1114/xwiki/bin/export/aa/WebHome?format=odt] WARN  o.x.x.XMLUtils                 - Failed to apply XSLT transformation: [Assigning null to handle]
2020-03-27 16:47:38,686 [http://localhost:1114/xwiki/bin/export/aa/WebHome?format=odt] WARN  c.x.x.w.XWikiAction            - Uncaught exception: Error number 11015 in 11: Exception while exporting
com.xpn.xwiki.XWikiException: Error number 11015 in 11: Exception while exporting
        at com.xpn.xwiki.web.ExportAction.render(ExportAction.java:94)
        at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:560)
        at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:250)
        at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
        at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
        at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
        at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at com.xpn.xwiki.web.ActionFilter.doFilter(ActionFilter.java:112)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.wysiwyg.filter.ConversionFilter.doFilter(ConversionFilter.java:109)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SetHTTPHeaderFilter.doFilter(SetHTTPHeaderFilter.java:63)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SavedRequestRestorerFilter.doFilter(SavedRequestRestorerFilter.java:208)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.container.servlet.filters.internal.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:111)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:132)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:688)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1639)
        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:834)
Caused by: java.lang.NullPointerException: null
        at com.xpn.xwiki.internal.export.OfficeExporter.exportXHTML(OfficeExporter.java:107)
        at com.xpn.xwiki.internal.export.OfficeExporter.exportXHTML(OfficeExporter.java:82)
        at com.xpn.xwiki.pdf.impl.PdfExportImpl.exportHtml(PdfExportImpl.java:173)
        at com.xpn.xwiki.pdf.impl.PdfExportImpl.export(PdfExportImpl.java:159)
        at com.xpn.xwiki.web.ExportAction.export(ExportAction.java:184)
        at com.xpn.xwiki.web.ExportAction.render(ExportAction.java:91)
        ... 45 common frames omitted