Leading halachic authorities have ruled that online authorizations are acceptable for the purpose of selling chametz. The traditional and preferred practice, however, is for the authorization transaction to be done in person with the local rabbi.
Chabad.org makes this service available online at no charge, to provide every Jew with the opportunity to have their chametz sold for Passover.
This is not new, it has been done before.
They’ve been offering it for years.
Straggler hall of fame.