Dark Golden/Freestyle notes

[ShTHfan1]

So when playing around in the editor, I happened to notice that the hotkeys for the golden notes and freestyle notes were given a new function. That being, if you hit them twice, the note turns black. But neither seem to do anything. The dark golden note is just a regular golden note, and the dark freestyle note counts the same as a regular note. Is there any reason for that, or is this like an inbetween thing? Like the dark golden notes will have more weight in the future, or the dark freestyle notes are going to be optional or something like that?

I've got to admit, I'm intrigued as to what these mean! But whatever they mean, they seem to be missing a texture. Specifically, at the end of the note... :-\