of course trying to get the key added so the thing will build is another matter.. but at least that's the correct program from the aur ...
gpg --keyserver certserver.pgp.com --recv-keys EF6E286DDA85EA2A4BA7DE684E2C6E8793298290
def does not work
neither does
sudo pacman-key --keyserver pgp.mit.edu --recv-keys EF6E286DDA85EA2A4BA7DE684E2C6E8793298290 && sudo pacman-key --lsign-key EF6E286DDA85EA2A4BA7DE684E2C6E8793298290
BUT this ONE does WORK
gpg --keyserver hkps://keys.openpgp.org/ --recv-keys EF6E286DDA85EA2A4BA7DE684E2C6E8793298290
AND this ONE works
sudo pacman-key --keyserver hkps://keys.openpgp.org/ --recv-keys EF6E286DDA85EA2A4BA7DE684E2C6E8793298290 && sudo pacman-key --lsign-key EF6E286DDA85EA2A4BA7DE684E2C6E8793298290