Custom domain template with no sections: Impossible to display the Summary of documents

Steps to reproduce:

• In Studio, create a StructureTemplate for Domain, or edit existing one (if you had the DM template installed for example)
• Remove the SectionRoot part
• Save

Server side:

• Update the server with this config
• Create a new domain, for example "MyNewDomain"
• In "Workspaces", create a new workspace
• In this domain, create a File
• When saving the document => an error with the big hell in the log (see attachment): 3835 lines!

I tested misc. variations (including starting form a fresh new db) and always had the same issue.

Looks like the log is about a problem where nuxeo (widget(s) in thje Summary) can't find sections:

Failed to resolve document ref: /default-domain/sections
Publication tree DefaultSectionsTree-default-domain is not available : check config
Error Rendering View[/view_documents.xhtml]
com.sun.facelets.tag.TagAttributeException: /widgets/summary/comments_count_widget_template.xhtml @7,123 value="#{commentManagerActions.getCommentsAsThreadOnDoc(fieldOrValue).size}" /widgets/summary/comments_count_widget_template.xhtml @7,123 value="#{commentManagerActions.getCommentsAsThreadOnDoc(fieldOrValue).size}": java.lang.RuntimeException: org.nuxeo.ecm.core.api.ClientException:
java.lang.RuntimeException: Cannot register synch handler in current tx
[. . .]

and this triggers a lot of problem.

So:

• Is it a bug (hence, this ticket)? So it should be fixed for 5.9.6 I think (that's why I'm setting the level to "Major")
• Or do I have to do something special when I don't want to use sections, of at least don't want to use a SectionRoot whose node name is exactly "sections"? If yes, what? An XML extension?

(tested on 5.9.5 and 5.9.6 of today, 2014-09-12)