That's what struck me. She appeared to have appy characteristics. Those mean an app somewhere in the background. Or a quarter horse mare that throws apps. The quarter horse registry just changed it's regs I think to allow registering excess white, although that wouldn't carry over to app coloring. The app registry will not register excess white.
However, unless you are going into the horse business and want to start selling horses, it doesn't matter if there are papers or not.
I found 2. I don't see any white around her eyes but her hoofs are two toned. You can see the back one and I'll post another.