Steps to reproduce:

• Create new project
• Add class Foo
• Modify the header:
  Foo.h

  #include <list>
  
  class Bar;
  using namespace std;
  
  class Foo
  {
  public:
    Foo();
    list<Bar> baz();
    void baz2(list<Bar> bar);
    list<Bar>::iterator baz3();
    void baz4(list<Bar>::iterator bar);
  };
  

• Use "right click -> refactor -> add definition in Foo.cpp" for all 4 added methods
• The generated code goes as such:
  Foo.cpp

  #include "foo.h"
  
  Foo::Foo(){} // Fine
  list<Bar> Foo::baz(){} // Fine
  void Foo::baz2(list<Bar> bar){} // Fine
  list::iterator Foo::baz3(){} // Missing template argument
  void Foo::baz4(list::iterator bar){} // Missing template argument
  

The same thing happens when using "add definition outside class"