I investigated more about and I found this:
https://docs.joomla.org/How_to_determine_if_the_user_is_viewing_the_front_page
Then, I applied the fix in \plugins\system\nomadpro\nomadpro.php
I changed
private function getMenu() {
$app = JFactory::getApplication();
$this->menu = $app->getMenu();
$this->home = $this->menu->getDefault();
$this->current = $this->menu->getActive();
}
to
private function getMenu() {
$app = JFactory::getApplication();
$lang = JFactory::getLanguage();
$this->menu = $app->getMenu();
$this->home = $this->menu->getDefault($lang->getTag());
$this->current = $this->menu->getActive();
}
The plugin is now working also in my multilanguage file and I suggest to include this fix in the future release of Nomad.
Hope it could be useful!