okay
there are two contacts points to the glass, one on the outside is what Tony mentioned . If you pull off the outside lower weatherstrip (one screw on inside top of door, rest are clips that pull out) you will see this wear area.
That strip will cost about 50.00 and is still available from Ford. If your glass is already scratched , you can change out the molding before it gets worse.
The other point is a felt pad that contacts the inside glass. If that has a chunk of dirt on it then your tint can suffer as well. Just peel back the weather strip inside and out and peek in there to see the felt pad. Just be carefull pulling that strip off if you intend to re-use it because you can bend it close to the door handle easily.
Andy