Ticket #37007: 37007.3.diff

src/wp-trackback.php

@@ -91 +92 @@
 }
 
 if ( !empty($tb_url) && !empty($title) ) {
+        /**
+        * Fires before the trackback is added to a post.
+        *
+        * @since 4.7.0
+        *
+        * @param int    $tb_id     Post ID related to the trackback.
+        * @param string $tb_url    Trackback URL.
+        * @param string $charset   Character Set.
+        * @param string $title     Trackback Title.
+        * @param string $excerpt   Trackback Excerpt.
+        * @param string $blog_name Blog Name.
+        */
+        do_action( 'pre_trackback_post', $tb_id, $tb_url, $charset, $title, $excerpt, $blog_name );
+
         header('Content-Type: text/xml; charset=' . get_option('blog_charset') );
 
         if ( !pings_open($tb_id) )