Dimethicone is a non-greasy occlusive silicone based polymer that is a man-made synthetic molecule made up of repeating units called monomers. It also has been shown time and time again to be non-comedogenic, yet it provides a significant amount of emollience and coverage to the skin, without adding any heaviness.
Pore clogging ingredients are everywhere. If a product touts the label “non-comedogenic” don’t believe it if you suffer from acne. I can show you a whole list of products with this ”dermatologist approved” insignia, and they all contain pore clogging ingredients that will surely break you out.