moorscode
diff --git a/Collapse file
‎src/wp-includes/compat.php‎
Copy file name to clipboardExpand all lines: src/wp-includes/compat.php
+4Lines changed: 4 additions & 0 deletions b/Collapse file
‎src/wp-includes/compat.php‎
Copy file name to clipboardExpand all lines: src/wp-includes/compat.php
+4Lines changed: 4 additions & 0 deletions
@@ -79,6 +79,10 @@ function mb_substr( $str, $start, $length = null, $encoding = null ) {
  * @return string Extracted substring.
  */
 function _mb_substr( $str, $start, $length = null, $encoding = null ) {
+	if ( null === $str ) {
+		return '';
+	}
+
 	if ( null === $encoding ) {
 		$encoding = get_option( 'blog_charset' );
 	}