micheleadmin

Yep, it works smooth now.
Thank you so much for your precious support!
Best,
Michele

Update, in case it helps:
The piece of code it refers to is:

// if no filter selected
				if(isset($filter_keys)) {
					if(count($filter_keys) == 0) $filter_keys = 1;
				} else {
					$filter_keys = 1;
				}

Line 117 is the one that contains the second IF clause.
I am using Newspaper theme