This hook allows control over embedding of images from remote hosts when generating emails. In some circumstances you may not want to embed the remote image – perhaps due to slow performance from the remote server.
function disallowed_host( $allowed, $host ) { // return false; // if you want to link rather than embed all remote images if ( 's.w.org' === $host ) { $allowed = false; } return $allowed;}add_filter( 's2_remote_embed_host', 'disallowed_host', 10, 2 );