Chestnut definitely. As for her pattern, she looks like a tobiano. She could be a tovero, but it would depend on what her parents were as to whether she would be a true tovero. In other words, one parent would have to be a tovero, or one a tobiano & the other an overo. There's a good website I know of that i'll have to give ya...
Her mane and tail don't look flaxen to me. They look white because of her pattern there is white. On the forelock it looks chesnut. And then can have manes and tails that are a few shades lighter and not be flaxen, so she looks like a regular Chesnut paint/pinto since i'm not sure if she is registered. As for pattern i'm not sure, I don't know patterns well. Although she looks Tobiano to me
I believe those that said tovero are mistaking the face marking as a bald face in which it would have to extend too or past the inside corner of one or both eyes. She doesn't hold the markings of an Overo.
If you really want to look more into her color though(not pattern) than you can always do a genetic test with UC Davis. Horse Tests