The members of strong enum are listed in namespace that contains enum itself.

Example code:
namespace test{
  enum Weak {
    weak1, //!< 0
    weak2  //!< 1
  };
  enum class Strong {
    strong1, //!< 0
    strong2  //!< 1
  };
}

Expected result: strong1, strong2 are not documented in namespace "test". Only weak1, weak2 are listed as members of "test".

Result: weak1, weak2, strong1 and strong2 are all documented as members of namespace "test".