STL.natvis contains visualizers for _Ref_count_obj and _Ref_count_obj_alloc:

However, we've upgraded those control blocks (which is possible while preserving binary compatibility because shared_ptr performs type erasure). The modern forms are _Ref_count_obj2 and _Ref_count_obj_alloc3, which we don't have visualizers for:


Thus, while we intended for make_shared and allocate_shared to be visualized in cool ways, this has been broken for a while.