Edge case:

Conditions:
- default page is hidden from menu
- action=breadcrumbs
- showall = false (default)
- no other parameters 

First items in the $nodelist array is empty which gives a notice like:
Notice: Trying to get property 'current' of non-object in/error



modules\Navigator\action.breadcrumbs.php line 97

    // add in the 'default page'
    if( !$have_stopnode && $stopat == $this::__DFLT_PAGE ) {
        // get the 'home' page and push it on the list
$dflt_content_id =
ContentOperations::get_instance()->GetDefaultContent();
        $node = $hm->GetNodeById($dflt_content_id);
$pagestack[$dflt_content_id] =
Nav_utils::fill_node($node,$deep,0,$showall);  <-- should check for a return
value
    }