Just horsing around
Although we can’t communicate with animals through words, we often interpret our pets’ and other animals’ feelings by observing their actions and body language. This horse apparently did not want her mane braided, but her rider insisted on doing so anyway. In retaliation, the horse did something absolutely hilarious and unexpected.
She went over to get a drink of water, and then spit it into her rider’s boots, as retaliation. That’s one way to teach a human not to mess with your mane. It makes you wonder whether spitting water in someone’s shoe is the horse equivalent of saying, “I told you so.”