Ticket #57728: 57728.diff

src/wp-includes/formatting.php

@@ -4859 +4859 @@
                         break;
 
                 case 'gmt_offset':
-                        $value = preg_replace( '/[^0-9:.-]/', '', $value ); // Strips slashes.
+                        if ( is_string( $value ) ) {
+                                $value = preg_replace( '/[^0-9:.-]/', '', $value ); // Strips slashes.
+                        }
                         break;
 
                 case 'siteurl':