i know they are molting and it is probably hard to tell, but it is white
What does pasty butt look like
I traded one of my roosters for a hen who had pasty butt. She had gotten into some turkey feed and her poop was very runny. We just had to check to see if it was getting better and if there was any weird stuff stuck to her rear end, we would have to take a rag and just rub it to get the stuff off. I can't tell if your chicken has pasty butt but I hope she is okay!