"Windows operating system" firewall alert

I learned reading forum that Windows operating system alert is Comodo saying something is trying to access internet but it can’t determine which process - it is hidden.

This started happening to me just few days ago, and since I got at least 10-15 alerts. What could it be? Malware? Windows 10? How come I can’t remember ever getting such prompt in the past. Suggests something new is happening.

Is there a way to determine which process is doing that? So far I’m blocking connections and nothing visibly is happening.

Is it IN- or OUTgoing?