wp-includes/class-wp-matchesmapregex.php:86preg_replace_callback hook
$matchesarraystring public function callback( $matches ) { $index = (int) substr( $matches[0], 9, -1 ); return ( isset( $this->_matches[ $index ] ) ? urlencode( $this->_matches[ $index ] ) : '' ); }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-matchesmapregex.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.