<Headers> not is not shown in Project tree

QtCreator 4.4.1 shows a <Headers> node in the Project tree. It contains headers not explicitly mentioned in CMakeLists.txt. I believe this is a feature introduced in 4.3.

Opening the same project in 4.5.0-beta1 does not show this node. Everything else seems to work properly. I used the same project, same build dir, CMake version etc.