Exterior window treatments

I get it about condensation and the why of it. But are there any products to apply to the exterior of cabin glass to lessen the condensation? The outsides of my front windows fog up badly on very humid mornings to the point I need to roll down the windows. Probably nothing can be done about that. My rear center glass also fogs up badly due to -- I'm convinced -- the effects of my headache rack on airflow. The sections behind the passenger and driver with the wire mesh of the rack don't fog up nearly as badly as the 'open' center section.

 

Rain X makes something for "Anti Fog". I haven't tried it yet but I saw it the other day at the store.

 

Isn’t that what the defrost setting is for ?

 

A/C full bore + hot, humid outside air = condensation on the outside of the glass.
Front defroster uses A/C to defog the inside (blowing drier, cooler sir) BUT it also cools the glass enough to get condensation on the outside.
Warmer temp inside will likely lessen the annoying problem.