Hello
I just want to report that custom skins presently aren't working for me and I've tried on a clean Minecraft instance as well, it's always just the purple dog. If there are additional steps then there needs to be more info at the very least, but here's an example of what I imagine is me doing it correctly:

I have no idea why this is the case (and it shouldn't be) but after some testing I found it only finds textures that are in folder resource packs not zip packs. Try unzipping your resource pack and trying.

So is there a way I can workaround this until it's fixed? I have trouble working without instructions..

"unzipping your resource pack". Right click, zip file, -> Extract All -> Extract. And select the none zip version in the resource packs menu.