Solicitud de curso

Se ha producido un error al procesar la plantilla. 
The following has evaluated to null or missing:
==> curPage.getExpandoBridge().getAttribute("Abrir en nueva pestana")  [in template "20202#20242#10876295" at line 11, column 26]

----
Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing</#if>. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??
----

----
FTL stack trace ("~" means nesting-related):
	- Failed at: #if curPage.getExpandoBridge().getAtt...  [in template "20202#20242#10876295" at line 11, column 21]
----
1<#-- Obtener las URLs base --> 
2<#assign publicURL = portalUtil.getPathFriendlyURLPublic()> 
3<#assign siteFURL = layout.getGroup().getFriendlyURL()> 
4 
5<div class="zona"> 
6    <#if entries?has_content> 
7        <div class="selectSiteMap contenido-right"> 
8            <#list entries as curPage> 
9                <#if !curPage.isHidden()> 
10                    <#-- Comprobamos si tiene el Expando "Abrir en nueva pestana" --> 
11                    <#if curPage.getExpandoBridge().getAttribute("Abrir en nueva pestana") == true> 
12                        <div class="sitemap-pestana">     
13                            <a href="${publicURL}${siteFURL}${curPage.getFriendlyURL(locale)}" 
14                               title="${curPage.getName(locale)}" 
15                               target="_blank"> 
16                                ${curPage.getName(locale)}   
17                            </a> 
18                        </div> 
19                    <#else> 
20                        <div class="sitemap-pestana">     
21                            <a href="${publicURL}${siteFURL}${curPage.getFriendlyURL(locale)}" 
22                               title="${curPage.getName(locale)}"> 
23                                ${curPage.getName(locale)}   
24                            </a> 
25                        </div> 
26                    </#if> 
27                </#if> 
28            </#list> 
29        </div> 
30    </#if> 
31</div>