P-DoFF (pronounced peed-off) is an acronym for Double face feet and palm. It's a type of reaction an average person with a reasonable understanding of anything would make in the face of utter dumbness. In particular, to the kind of things, David Avocado Wolfe says.
Random guy: David Avocado Wolfe said solar panels absorb light and it's lost forever. So it's not renewable energy and so cruel for the sun.
Fifth-grader: Dude, I'm just P-DoFF (peedoff) right now. That shit is bonkers af.