truth be told I grew up with a mix of the blond/white feather look, depending on the comic- and yes, I prefer the blond! However, my argument for it being the more canon of the two is that in every oil painting Carl Barks did he gave Gladstone blond coloured feathers- we also have to remember that he didn’t have a huge amount of control over what colours the comics were given, so while he may have striven to imply it with the contouring and curls he drew Gladstone’s hair with, the process of colouring them yellow may have been thought too complex/ignored by the colourists of the comics