Display members of class, itself generating a vector, member of a class, used in a branch

ROOT
1

Dear rooters,

my two questions are loosely summarized in the subject…

I create a TTree with a branch that contains a class Physics, i.e. this kind of approach:
https://root.cern.ch/doc/master/classTTree.html#addingacolumnofobjs
Now this class Physics has as a member a vector of class Data, here is a simplified example:

class Data {
public:
  Data(){};
  ~Data(){};
  friend std::ostream& operator<<( std::ostream& os, const Data& NPPData );
public:
  unsigned short ID;
public:
  Data(unsigned short ID_) : ID(ID_) {};
  ClassDef(Data, 1)  
}

class Physics {
private:
  vector<Data> NP;
public:
  Physics(){};
  ~Physics(){};
  friend std::ostream& operator<<( std::ostream& os, const Physics& NPP);
  ClassDef(Physics, 1) 
}

I also have a linkdef.h file to generate the dictionary:

#ifdef __CINT__
#pragma link off all globals;
#pragma link off all classes;
#pragma link off all functions;
#pragma link C++ class Data+ ;
#pragma link C++ class Physics+ ;
#pragma link C++ class vector<Data>+ ;
#endif

Everything compile, the TTree is generated and I can draw the member of the Data class, i.e.

tree->Draw("NP.ID")
tree->Scan("NP.ID","","",5)
***********************************
*    Row   * Instance *     NP.ID *
***********************************
*        0 *        0 *           *
*        1 *        0 *           *
*        2 *        0 *           *
*        3 *        0 *        90 *
*        3 *        1 *        66 *
*        3 *        2 *        38 *
*        3 *        3 *        18 *
*        3 *        4 *        89 *
*        3 *        5 *        41 *
*        3 *        6 *        19 *
*        4 *        0 *           *
***********************************

works and give me what I expect.
Now I would like to see the details of Data members when I do a Print, but as you can see below the display stops at vector<Data> :

******************************************************************************
*Tree    :PhysicsTree:                                                              *
*Entries : 13877025 : Total =      1244231045 bytes  File  Size =  322446257 *
*        :          : Tree compression factor =   3.86                       *
******************************************************************************
*Branch  : Physics                                                                                *
*Entries : 13877025 : BranchElement (see below)                              *
*............................................................................*
*Br    0 :NP        : vector<Data>                                                           *
*Entries : 13877025 : Total  Size=  483516781 bytes  File Size  =  196297478 *
*Baskets :     1500 : Basket Size=   25600000 bytes  Compression=   2.46     *
*............................................................................*

I would like the corresponding line to look like:

*Br    0 :NP        : vector<Data>           .ID/I                                                *

Is it possible? And if yes, what am I missing? Note that I can not access the splitlevel of the branch as this is located in a common code for all collaborators (my code in embedded in a much bigger one).

When I use “TBrowser” I can see the leaves but then I have the following error message:

Error in <TClass::LoadClassInfo>: no interpreter information for class Data is available even though it has a TClass initialization routine.

I checked the forum for this error but could not find a similar case as mine. What I am missing?
Thank you very much in advance

ROOT Version: 6.28/06
Platform: Linux ubuntu20 5.4.0-187-generic
Compiler: linuxx8664gcc