ist-paragraph-list-template-W

Si è verificato un errore nell'elaborarazione del modello. 
Can't compare values of these types. Allowed comparisons are between two numbers, two strings, two dates, or two booleans.
Left hand operand is an extended_hash (wrapper: com.liferay.portal.template.freemarker.internal.LiferayTemplateModel).
Right hand operand is a string (wrapper: f.t.SimpleScalar).
The blamed expression:
==> elem2!=""  [in template "20116#20152#232491048" at line 21, column 43]

----
FTL stack trace ("~" means nesting-related):
	- Failed at: #if elem2?has_content && elem2 != ""  [in template "20116#20152#232491048" at line 21, column 17]
----
1<div class="ist-paragraph-list"> 
2 
3    <#if title.getSiblings()?has_content> 
4    	<#list title.getSiblings() as cur_title> 
5    		<h2>${cur_title.getData()}</h2> 
6    		 
7    		<#if cur_title.listElement1.getSiblings()?has_content> 
8    		    <#assign first1 = cur_title.listElement1.getSiblings()?first > 
9    		    <#if first1?has_content && first1.getData()?trim?has_content> 
10    		    <ol class="ol-ist-paragraph-list"> 
11        		    <#list cur_title.listElement1.getSiblings() as list_1> 
12        		        <#if list_1?has_content && list_1.getData()?trim?has_content> 
13        		        <li class="li-ist-paragraph-list"> ${list_1.getData()}</li> 
14        		        </#if> 
15        		    </#list> 
16    		    </ol> 
17    		    </#if> 
18    		</#if> 
19    		     
20    		<#assign elem2 = (cur_title.listElement2)!""> 
21    		<#if elem2?has_content && elem2!=""> 
22        		<#if cur_title.listElement2.getSiblings()?has_content> 
23        		    <#assign first2 = cur_title.listElement2.getSiblings()?first > 
24        		    <#if first2?has_content && first2.getData()?trim?has_content> 
25        		    <ol class="ol-ist-paragraph-list"> 
26            		    <#list cur_title.listElement2.getSiblings() as list_2> 
27            		        <#if list_2?has_content && list_2.getData()?trim?has_content> 
28            		        <li class="li-ist-paragraph-list"> ${list_2.getData()}</li> 
29            		        </#if> 
30            		    </#list> 
31        		    </ol> 
32        		    </#if> 
33        		</#if> 
34    		</#if> 
35    	</#list> 
36    </#if> 
37</div> 

space-template-w