How to reproduce it :

• I configured link directory into a skin :

1. Into the header.xsl, import :

    <xsl:import href="plugin:link-directory://pages/services/directory/utils/thumbnails_utils.xsl"/>

1. Into the header.xsl, add :

    <xsl:apply-templates select="cms/inputData/linkDirectory[@id='topMenu']/links/link" mode="thumbnails"><xsl:apply-templates select="cms/inputData/linkDirectory[@id='topMenu']/links/link" mode="thumbnails">                     <xsl:with-param name="uniqueId" select="$uniqueId"/>                 </xsl:apply-templates>

1. Into the head.xsl, add into the common-script template :

 <xsl:call-template name="link-dynamic-info-js">
            <xsl:with-param name="themes" select="/cms/inputData/linkDirectory/themes"/>
        </xsl:call-template>

1. Add in the conf/ folder, the attachment file link-directory.xml
2. In the cms/_admin, configure the messaging tab of the main configuration
3. Into WEB-INF/param/runtime.xml, use :

   <org.ametys.plugins.messagingconnector.MessagingConnector>org.ametys.plugins.exchange.GraphConnector</org.ametys.plugins.messagingconnector.MessagingConnector> 

Configure links into the link directory tool of the CMS with the expected theme TOP_MENU
Preview : on load, an error occurs :

 Date:			Tue Mar 02 09:55:13 CET 2021 (1614675313782)
Thread:		http-nio-10020-exec-8
Message #:	32145
Level:		ERROR
NDC:			
Category:	org.ametys.runtime.servlet.RuntimeServlet
Message:		Internal Cocoon Problem
Location:	org.ametys.runtime.servlet.RuntimeServlet.service(RuntimeServlet.java:584)
Thrown:
java.lang.StackOverflowError
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:79)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)
	at org.ametys.core.util.SizeUtils._sizeOf(SizeUtils.java:126)

The events of the calendar are however well displayed after a delay