diff --git a/wp-includes/formatting.php b/wp-includes/formatting.php
index b442b0b151..ebb20d6a8e 100644
--- a/wp-includes/formatting.php
+++ b/wp-includes/formatting.php
@@ -3040,7 +3040,9 @@ function wp_rel_nofollow_callback( $matches ) {
 function wp_targeted_link_rel( $text ) {
 	// Don't run (more expensive) regex if no links with targets.
 	if ( stripos( $text, 'target' ) !== false && stripos( $text, '<a ' ) !== false ) {
-		$text = preg_replace_callback( '|<a\s([^>]*target\s*=[^>]*)>|i', 'wp_targeted_link_rel_callback', $text );
+		if ( ! is_serialized( $text ) ) {
+			$text = preg_replace_callback( '|<a\s([^>]*target\s*=[^>]*)>|i', 'wp_targeted_link_rel_callback', $text );
+		}
 	}
 
 	return $text;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index b3f7b9e407..7b5eba7173 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.3-alpha-45407';
+$wp_version = '5.3-alpha-45408';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.