Remove WordPress Pingback Emails From Your Own Domain

/**
 * Disable self-pingbacks (pingbacks from your own domain)
 */

function disable_self_pingbacks(&$links) {
    $home_url = get_option('siteurl');
    
    $parsed_home = parse_url($home_url);
    $home_domain = isset($parsed_home['host']) ? $parsed_home['host'] : '';
    
    $home_domain = preg_replace('/^www\./', '', $home_domain);
    
    foreach ($links as $key => $link) {
        $parsed_link = parse_url($link);
        $link_domain = isset($parsed_link['host']) ? $parsed_link['host'] : '';
        
        $link_domain = preg_replace('/^www\./', '', $link_domain);
        
        if ($home_domain == $link_domain) {
            unset($links[$key]);
        }
    }
}
add_action('pre_ping', 'disable_self_pingbacks');

// XML RPC

function block_self_pingback_xmlrpc($source_uri) {
    $home_url = get_option('siteurl');
    
    $parsed_home = parse_url($home_url);
    $parsed_source = parse_url($source_uri);
    
    $home_domain = isset($parsed_home['host']) ? $parsed_home['host'] : '';
    $source_domain = isset($parsed_source['host']) ? $parsed_source['host'] : '';
    
    $home_domain = preg_replace('/^www\./', '', $home_domain);
    $source_domain = preg_replace('/^www\./', '', $source_domain);
    
    if ($home_domain == $source_domain) {
        return false;
    }
    
    return $source_uri;
}
add_filter('xmlrpc_pingback_source_uri', 'block_self_pingback_xmlrpc');

// Prevent pingback emails from being sent about internal links on my own domain

function disable_self_pingback_emails($notify, $comment_id) {
    $comment = get_comment($comment_id);
    
    if ($comment && in_array($comment->comment_type, array('pingback', 'trackback'))) {
        $source_url = $comment->comment_author_url;
        
        $home_url = get_option('siteurl');
        
        $parsed_home = parse_url($home_url);
        $parsed_source = parse_url($source_url);
        
        $home_domain = isset($parsed_home['host']) ? $parsed_home['host'] : '';
        $source_domain = isset($parsed_source['host']) ? $parsed_source['host'] : '';
        
        $home_domain = preg_replace('/^www\./', '', $home_domain);
        $source_domain = preg_replace('/^www\./', '', $source_domain);
        
        if ($home_domain == $source_domain) {
            return false;
        }
    }
    
    return $notify;
}
add_filter('notify_post_author', 'disable_self_pingback_emails', 10, 2);

function remove_pingback_header() {
    if (isset($_SERVER['HTTP_X_PINGBACK'])) {
        unset($_SERVER['HTTP_X_PINGBACK']);
    }
}
add_action('init', 'remove_pingback_header');

remove_action('wp_head', 'rsd_link');
remove_action('wp_head', 'wlwmanifest_link');