Not sure what they are called, the elongated buttons that move the horizontal and vertical scroll bars contrast so little with the white background of the scroll bars themselves that I often struggle to see them. Is there a way to darken those buttons down a bit to make them stand out?
Those are called “thumbs”, funnily enough. We’re aware that if you run macOS in Dark Mode and you have scroll bars set to appear always in System Preferences that the thumbs can appear almost white, and this is something we will address in a future update.