* @return string
*/
public function replace( $subject ) {
- if ( function_exists( 'fss_prep_replace' ) ) {
+ if (
+ function_exists( 'fss_prep_replace' ) &&
+ version_compare( PHP_VERSION, '5.5.0' ) < 0
+ ) {
if ( $this->fss === false ) {
$this->fss = fss_prep_replace( $this->data );
}