I have a Lazarus program that calls an external exe using TProcessUtf8.  I send filename(s) as parameter(s) to the external exe.  After upgrading Lazarus to version 2.0 I get errors if these filenames contain utf8 characters.  Is this a bug in Lazarus?  Or have anything changed from Lazarus v. 1.8.2 to 2.0, so that my code must be changed accordingly?

This is Windows 10 and Lazarus 2.0 downloaded from Lazarus site. Unit starte with this (if it matters):

unit UnitMain;
{$mode objfpc}{$H+}
interface
uses
  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, ComCtrls,
  StdCtrls, ExtCtrls, Grids, Process,
  {$IFDEF WINDOWS} Utf8Process, {$ENDIF}
  Types, LCLTranslator;