Unusual Bird: Female house finch with partial leucism

This partially leucistic female house finch began showing up at my backyard feeders a few weeks ago. There does not appear to be any bullying towards her from the other house finches, at least not any more than what normally occurs from a bird looking for an already occupied perch. The white on her face is not symmetrical on both sides of her head – it is primarily on the left side, giving somewhat of a “Phantom of the Opera” mask type of appearance to her.