Ticket #32619: 32619.6.patch

src/wp-includes/link-template.php

@@ -3621 +3621 @@
         } elseif ( $id_or_email instanceof WP_Post ) {
                 // Post Object
                 $user = get_user_by( 'id', (int) $id_or_email->post_author );
-        } elseif ( $id_or_email instanceof WP_Comment ) {
+        } elseif ( $id_or_email instanceof WP_Comment || ( is_object( $id_or_email ) && isset( $id_or_email->comment_ID ) ) ) {
                 /**
                  * Filter the list of allowed comment types for retrieving avatars.
                  *