Tousknot headlights on Hyundai Sonata NF when turning on rear glass heating

The point is that simultaneously with the heating of the rear glass at Hyundai Sonata NF, the heating of mirrors and the area of the windshield is included, leading to a short voltage drop in the vehicle's onboard network. That's why the headlights are dull for a few seconds. This behaviour does not indicate any malfunction in the electrical equipment of the vehicle.