Okienko szczegółów and other 80,800 icons from Icons8 icon pack follow the visual guidelines of the operating systems: Windows, iOS, Android KitKat, and Material. PNG format is free up to 100x100 px. Icons are availble for download in PNG and vector (SVG, PDF, EPS, and more).
The image is a square that looks like a sheet of paper. There are four dashes in a vertical line on the left. To the right of the dashes are four vertical lines. There is one line to each dash. The lines and dashes are on the sheet. At the bottom of the sheet the edge comes to a point.