GraphDB's Visual graph does not display all triples

In my graph I have the following assertions

  @prefix :     <http://www.example.org/~joe/contact.rdf#> .
  @prefix foaf: <http://xmlns.com/foaf/0.1/> .
  @prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

  :joesmith a foaf:Person ;
        foaf:givenname "Joe" ;
        foaf:family_name "Smith" ;
        foaf:homepage <http://www.example.org/~joe/> ;
        foaf:mbox <mailto:joe.smith@example.org> .

I loaded the graph in GraphDB.

If I point the GraphDB's Visual Graph to :joesmith, I would like to see all the triples but I see this graph

foaf:givenname and foaf:family_name are not shown in the graph but they are in node details tab, and it's ok.

Instead the node http://www.example.org/~joe/ is not connected to :joesmith. It seems pretty wired, since there is an explicit assertion belonging to :joesmith

Is this a bug or a problem in my data?