function IsTaskbarBtnExist(h: HWND): Boolean;
var
  exstyle: Longint;
begin
  Result:= IsWindowVisible(h);
  if Result then
    begin
      exstyle := GetWindowLong(h, GWL_EXSTYLE);
      Result := exstyle and WS_EX_APPWINDOW <> 0;
      if not Result and
         (exstyle and WS_EX_TOOLWINDOW = 0) then
        Result := GetWindowLong(h, GWL_HWNDPARENT) = 0;
     end;
end;