Colours of Disney characters

My experience of traditional Disney characters such as Mickey Mouse, Donald Duck, and Goofy was from watching Disney movies and Saturday morning television as a child in the 1980s. In the colour cartoons Mickey Mouse and Goofy invariably had a pinkish, caucasian-like skin colour. And Donald Duck’s usual sailor suit was always blue. The Wikipedia articles for Mickey, Goofy, and Donald have several images with the characters coloured as I remember them.

However, I’ve recently started reading some Disney comic books for the first time, and have noticed that the characters are coloured differently. You can see from some scans of the comic book I’m reading that Mickey and Goofy have white skin, and Donald’s suit is black.

I’m wondering what accounts for this discrepancy. Regarding Mickey and Goofy, my first thought was that it was too difficult to reproduce pink skin with the four-colour Benday dots used for printing comics. But while this may have been true for the pulp comics of decades past, it certainly isn’t a problem with today’s printing technology. Indeed, the comic books I’m reading have lots of very smooth gradients and characters with accurate flesh tones. Are Mickey’s and Goofy’s albinism simply a holdover from 1950s printing technology? Or maybe some misguided attempt at political correctness by not wishing to depict them as unambiguously caucasian?

Donald’s clothing is even more of a mystery, since even with antiquated printing technology it would be easy to give him a solid blue shirt. Why is he dressed in black in the comics, but blue in other merchandise and in the animated cartoons?

In the comics, as far as I can recall, Mickey and Goofy were always white. That’s also true of most of the other pre-movie non-human characters – Minnie, Donald, Daisy, Black Pete, uncle Scrooge, Clarabelle Cow etc. The three pigs get to be flesh-colored, because that’s the “common” pig color.
Donald often is dressed in blue, but sometimes they vary it. I don’t know why. But hee’s certainly not invariably dressed in black in the comics.

Note, as well, that Newspaper comics, US comic books, and various foreign comic books are printed (and often written and drawn by ) different people. I’m not sure how much control has been placed over these details.