Expanding a package in JSF > Admin > Update Center > Marketpace packages raises an exception

freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> pkg.isSupported  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 39]

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Tip: It's the step after the last dot that caused this error, not those before it.
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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)??
----

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FTL stack trace ("~" means nesting-related):
        - Failed at: #if pkg.isSupported()  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 34]
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        at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.UnexpectedTypeException.newDesciptionBuilder(UnexpectedTypeException.java:85) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.UnexpectedTypeException.<init>(UnexpectedTypeException.java:48) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.NonMethodException.<init>(NonMethodException.java:49) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.MethodCall._eval(MethodCall.java:85) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Expression.eval(Expression.java:83) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Expression.evalToBoolean(Expression.java:161) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Expression.evalToBoolean(Expression.java:147) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.IfBlock.accept(IfBlock.java:49) ~[freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Environment.visit(Environment.java:330) [freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Environment.visit(Environment.java:336) [freemarker-2.3.28.jar:2.3.28]
        at freemarker.core.Environment.process(Environment.java:309) [freemarker-2.3.28.jar:2.3.28]

Caused by: org.nuxeo.ecm.platform.rendering.api.RenderingException: freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> pkg.isSupported  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 39]

----
Tip: It's the step after the last dot that caused this error, not those before it.
----
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 pkg.isSupported()  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 34]
----
        at org.nuxeo.ecm.platform.rendering.fm.FreemarkerEngine.render(FreemarkerEngine.java:199)
        at org.nuxeo.ecm.webengine.model.impl.AbstractWebContext.render(AbstractWebContext.java:641)
        ... 82 more
Caused by: freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> pkg.isSupported  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 39]

----
Tip: It's the step after the last dot that caused this error, not those before it.
----
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 pkg.isSupported()  [in template "file:/C:/nuxeo-server-10.10-tomcat/nxserver/web/root.war/modules/org.nuxeo.admin.center/skin/views/packageListingProvider/pkgDetails.ftl" at line 84, column 34]
----
        at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134)
        at freemarker.core.UnexpectedTypeException.newDesciptionBuilder(UnexpectedTypeException.java:85)
        at freemarker.core.UnexpectedTypeException.<init>(UnexpectedTypeException.java:48)
        at freemarker.core.NonMethodException.<init>(NonMethodException.java:49)
        at freemarker.core.MethodCall._eval(MethodCall.java:85)
        at freemarker.core.Expression.eval(Expression.java:83)
        at freemarker.core.Expression.evalToBoolean(Expression.java:161)
        at freemarker.core.Expression.evalToBoolean(Expression.java:147)
        at freemarker.core.IfBlock.accept(IfBlock.java:49)
        at freemarker.core.Environment.visit(Environment.java:330)
        at freemarker.core.Environment.visit(Environment.java:336)
        at freemarker.core.Environment.process(Environment.java:309)
        at org.nuxeo.ecm.platform.rendering.fm.FreemarkerEngine.render(FreemarkerEngine.java:194)
        ... 83 more