Adding the same material as referenced material to many materials fails at first

Add 3 spheres. Change the material properties of sphere 1. Set the material of sphere 1 as referenced material to sphere 2. Try to add it to sphere 3 as well -> does not work. Setting the reference to sphere 2's material first, and then to sphere 1's material works.

I suppose that is because the path to the previously set material is already shown in the "Path", there is no changed signal when setting the same, even though the target is different.