This extension makes it so questions that have been completed on the SAT website are dimmed out. Also has some quality of life features like selecting all questions / deselecting all questions. More things will be added later if needed. Seems minor, but something like this would have been a HUGE help back when I was studying for the SAT. VERY IMPORTANT: This extension DOES NOT mark questions completed prior to the installation of the extension. This is only useful if you install it before doing many questions.