rear screen misting up

It’s that time of year when the nights are getting colder and moisture is all over the car in the mornings. My question is, does anyone have any tips to stop the inside of the rear screen from misting over due to the condensation on the outside as it takes ages for the demister to clear the centre of it only to for it to mist up again as the rest of the rear screen is still covered?

from the last news http://ift.tt/12wBM6f

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