message: add information for the flatpak package
diff: @@ -134,6 +134,17 @@ UpdateDialog::UpdateDialog(
  // if (msgBox.exec() == QMessageBox::StandardButton::No)
  // return;
  }
  +#else
  + QMessageBox msgBox(this);
  + msgBox.setWindowTitle(tr("Flatpak download"));
  +
  + msgBox.setText(tr("If you have downloaded the package from flathub, please wait until the package will be updated there (about 1 day)."));
  + msgBox.setInformativeText(tr("Would you like to download the flatpak package anyway manuall? "));
  + msgBox.setStandardButtons(QMessageBox::StandardButton::Yes | QMessageBox::StandardButton::No);
  + msgBox.setDefaultButton(QMessageBox::StandardButton::No);
  + msgBox.setIcon(QMessageBox::Icon::Question);
  + if (msgBox.exec() == QMessageBox::StandardButton::No)
  + return;
  #endif
  // Start download.
  