Ticket #16894: 16894.3.diff

src/wp-includes/comment-template.php

@@ -2116 +2116 @@
                 } else {
                         $_comments = $wp_query->comments;
                 }
+
+                if ( ! $wp_query->comment_meta_cached ) {
+                        $comment_ids = wp_list_pluck( $_comments, 'comment_ID' );
+                        update_meta_cache( 'comment', $comment_ids );
+                        $wp_query->comment_meta_cached = true;
+                }
         }
 
         if ( '' === $r['per_page'] && get_option('page_comments') )

src/wp-includes/query.php

@@ -1293 +1293 @@
          public $thumbnails_cached = false;
 
         /**
+         * Set if comment meta has already been cached
+         *
+         * @since 4.4.0
+         * @access public
+         * @var bool
+         */
+         public $comment_meta_cached = false;
+
+        /**
          * Cached list of search stopwords.
          *
          * @since 3.7.0