This page shows the different variations of the Otwórz okno from an Icons8 icon pack. Feel free to resize and recolor the icon, and then download the icon in PNG format for free. Icons are available in PNG and vector.
This icon represents an open window. It is a large square with four smaller sqaures on each side. The sqaures on the side are one big on the bottom and one smaller one on the bottom to represent shutters.