First line in Console duplicated

ChangeConsole(TGUIConsole.Create(Memo1.Lines));
Console.Write('String');  // Set internal FLineBreak to False
Memo1.Lines.Clear;
Console.Write('Some String');  // Log have "Some StringSome String"
Reason in method 
procedure TGUIConsole.InternalWrite(const S: string; bWriteLine: Boolean);
var
  idx : Integer;
begin
  if FLineBreak then
  begin
    FMemo.Add( S );
  end else
  begin
    idx := FMemo.Count - 1;
    if idx < 0 then
    begin
      FMemo.Add( S );
    end;
    FMemo[idx] := FMemo[idx] + S;
  end;
  FLineBreak := bWriteLine;
end; 

FMemo[idx] := FMemo[idx] + S;

    if idx < 0 then
     begin
       FMemo.Add( S );
     end else
       FMemo[idx] := FMemo[idx] + S;