Bizarre, OP misses the simplest and most logical way of removing frost/ice, a scraper
Like most I start car, switch on rear and mirror demist, get out, scrape windows, get back in and drive off.
With talk of
maybe he lives in the North pole or is a serious mouth breather, cant say I have ever noticed this being a thing.
I suppose you could wind the window down as you set off if its that much of an issue for a couple of mins until the car is warming up
To be fair I have had internal freezing on very cold days in my Vivaro Minibus. Not sure if its breath or just moisture collected from day to day use.
In car dehumidifier helps. Or I run the air conditioning during the last few miles of the journey before I lay the bus up for the night to dry the air.