Ticket #49564: 49564.diff

src/wp-includes/ms-functions.php

@@ -1730 +1730 @@
                 $admin_email = 'support@' . $_SERVER['SERVER_NAME'];
         }
 
-        $from_name       = get_site_option( 'site_name' ) == '' ? 'WordPress' : esc_html( get_site_option( 'site_name' ) );
-        $message_headers = "From: \"{$from_name}\" <{$admin_email}>\n" . 'Content-Type: text/plain; charset="' . get_option( 'blog_charset' ) . "\"\n";
-        $message         = $welcome_email;
+        $from_name         = get_site_option( 'site_name' ) == '' ? 'WordPress' : esc_html( get_site_option( 'site_name' ) );
+        $message_headers   = array();
+        $message_headers[] = "From: \"{$from_name}\" <{$admin_email}>\n";
+        $message_headers[] = 'Content-Type: text/plain; charset="' . get_option( 'blog_charset' ) . "\"\n";
+        $message           = $welcome_email;
 
         if ( empty( $current_network->site_name ) ) {
                 $current_network->site_name = 'WordPress';
@@ -1750 +1752 @@
          */
         $subject = apply_filters( 'update_welcome_user_subject', sprintf( $subject, $current_network->site_name, $user->user_login ) );
 
+        /**
+         * Filters the headers of the welcome email after user activation.
+         *
+         * @since 5.5.0
+         *
+         * @param array   $message_headers  The email headers.
+         * @param string  $subject          The email subject.
+         * @param string  $message          The email content.
+         * @param WP_User $user             The user to be notified.
+         * @param array   $current_network  The current network.
+         */
+        $message_headers = apply_filters( 'update_welcome_user_headers', $message_headers, $subject, $message, $user, $current_network );
+
         wp_mail( $user->user_email, wp_specialchars_decode( $subject ), $message, $message_headers );
 
         if ( $switched_locale ) {