In Firefox, I also add the following to userChrome.css to make the scroll thumb high-contrast versus the scroll bar itself. The default Firefox colors are, in m

In Firefox, I also add the following to userChrome.css to make the scroll thumb high-contrast versus the scroll bar itself. The default Firefox colors are, in my opinion, too low-contrast. :root { scrollbar-color: rgb(35,75,240) rgb(220,222,224) !important; } The first color is for the thumb (the part you pick up and drag) and the second color is for the remainder of the scrollbar. Resulting appearance: https://imgur.com/a/A1LTS4M https://imgur.com/a/A1LTS4M