diff --git a/wp-includes/class-wp-customize-manager.php b/wp-includes/class-wp-customize-manager.php
index e53a6ec477..fe03a93c1e 100644
--- a/wp-includes/class-wp-customize-manager.php
+++ b/wp-includes/class-wp-customize-manager.php
@@ -4686,6 +4686,21 @@ final class WP_Customize_Manager {
 
 		if ( $this->return_url ) {
 			$return_url = $this->return_url;
+
+			$return_url_basename = wp_basename( parse_url( $this->return_url, PHP_URL_PATH ) );
+			$return_url_query    = parse_url( $this->return_url, PHP_URL_QUERY );
+
+			if ( 'themes.php' === $return_url_basename && $return_url_query ) {
+				parse_str( $return_url_query, $query_vars );
+
+				/*
+				 * If the return URL is a page added by a theme to the Appearance menu via add_submenu_page(),
+				 * verify that it belongs to the active theme, otherwise fall back to the Themes screen.
+				 */
+				if ( isset( $query_vars['page'] ) && ! isset( $_registered_pages[ "appearance_page_{$query_vars['page']}" ] ) ) {
+					$return_url = admin_url( 'themes.php' );
+				}
+			}
 		} elseif ( $referer && ! in_array( wp_basename( parse_url( $referer, PHP_URL_PATH ) ), $excluded_referer_basenames, true ) ) {
 			$return_url = $referer;
 		} elseif ( $this->preview_url ) {
@@ -4694,21 +4709,6 @@ final class WP_Customize_Manager {
 			$return_url = home_url( '/' );
 		}
 
-		$return_url_basename = wp_basename( parse_url( $this->return_url, PHP_URL_PATH ) );
-		$return_url_query    = parse_url( $this->return_url, PHP_URL_QUERY );
-
-		if ( 'themes.php' === $return_url_basename && $return_url_query ) {
-			parse_str( $return_url_query, $query_vars );
-
-			/*
-			 * If the return URL is a page added by a theme to the Appearance menu via add_submenu_page(),
-			 * verify that it belongs to the active theme, otherwise fall back to the Themes screen.
-			 */
-			if ( isset( $query_vars['page'] ) && ! isset( $_registered_pages[ "appearance_page_{$query_vars['page']}" ] ) ) {
-				$return_url = admin_url( 'themes.php' );
-			}
-		}
-
 		return $return_url;
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index ac3f007365..062b451610 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-54134';
+$wp_version = '6.1-alpha-54135';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.