4.2: blog: jahia in root context: I could not access to my blog pages any more

I have created my demo site (a template of each type, in multilang with some basic content and users) with the std jahia/Jahia context. Then I tried to migrate my environement to the Root context.

I now have some problem to display my blog page which returns 0 element while my parent blog_listing page correctly list all the element. So I can only access to my blog entries going through the global blog_listing page. Looks like something should be hardcoded to jahia/Jahia in the blog template.