Blackface bad; Whiteface good?

We read:

"An intriguing yet peculiar occurrence that has manifested in African American popular culture over the last two decades is the performance of whiteface or black actors portraying white characters. Often “dressed” in chalky white makeup and blue contact lenses, these caricatures of white folks often trouble or legitimize whiteness for a non-white audience.

On the surface, whiteface performers often exaggerate widely recognized and aesthetically pleasing aspects of white people and culture from a minority viewpoint – light eyes, light colored hair, swanky clothes, snobbish attitude. The ultimate aim, however, is to present the audience with how an Othered body subverts whiteness as normalized discourse.

Source

The above is of course written in nearly impenetrable "postmodernist" jargon but, with a great effort, I gather that blacks don whiteface makeup for the purpose of mocking whites. And that is just great, apparently.

But if the old blackface minstrel shows (which were intended to CELEBRATE Africans as entertainers as far as I can see) were "racist", then surely whiteface is racist too. I guess I am missing something.