diff --git a/functions/php_poly_fill.php b/functions/php_poly_fill.php
index b3872ec5746c563fd4ae9742eb9c1b2db397011e..829631fc482b2618b9466ce8c5312d7a7c788835 100644
--- a/functions/php_poly_fill.php
+++ b/functions/php_poly_fill.php
@@ -34,7 +34,7 @@ function pf_json_decode($json, $associative = null, $depth = 512, $flags = 0)
  * @return string[]|false
  */
 function pf_explode($separator, $string) {
-    if (is_blank($string))
+    if (is_blank($string) || empty($separator))
         return [''];
 
     return explode($separator, $string);