I have tried to use three texture packs that are only suppose to change the colormap/certain block textures and for some reason this causes the horse/donkey/mule textures to go back to their vanilla textures. All three are mcpacks that I edited but I did try with the uneditd version of the mcpacks (Cherry blossoms v2.0.0, Winter Season Addon, and Autumn Texture Pack) and the horse textures still dont work. I'm mainly using the Super Cute Pack from the marketplace but I also tried to get it to work with the other minecraft marketplace texture packs but the same problems happens , they worked before the update though so it has to be a bug because everything I do doesn't fix it, at least I'm hoping it's a bug because that's the only thing that could explain it.