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        protected override void WndProc(ref Message m) 
        {
            switch (m.Msg)
            {
                case WM_WINDOWPOSCHANGING :
                case WM_WINDOWPOSCHANGED:
                    // Do Nothing...
                    break;   
                Default:
                    base.WndProc(ref m);
            }
        }                    

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type
  TForm1 = class(TForm)
  protected
    procedure WndProc(var Message: TMessage) ; override;
  private
  end;

implementation
  
procedure TForm1.WndProc(var Message: TMessage) ;
begin
  case message.Msg of
    WM_WINDOWPOSCHANGING :;
    WM_WINDOWPOSCHANGED :;
    WM_SIZE :;
    WM_NCCALCSIZE :;
  else
    inherited;
  end;
end;                    

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procedure TForm1.WndProc(var Message: TMessage) ;
const
  TestCaption = false;

begin
  if not TestCaption then
  begin
    case message.Msg of
      WM_WINDOWPOSCHANGING : Log('WM_WINDOWPOSCHANGING');
      WM_WINDOWPOSCHANGED : Log('WM_WINDOWPOSCHANGED');
      WM_SIZE : Log('WM_SIZE');
      WM_NCCALCSIZE : Log('WM_NCCALCSIZE');
    else
      begin
        //Log('else');  <-- seems there is no way to get a log output working
        inherited;
      end;
    end;
  end
  else
  begin
    if Message.msg = WM_SETTEXT then
      Log('WM_SETTEXT : '+PChar(Message.LParam))
    else
    begin
      //Log('else'); <-- seems there is no way to get a log output working
      inherited WndProc(Message);
    end;
  end;
end;