Bug 216140

Created attachment 407908 [details] Screenshots of the issue On iOS 13, when the contents of body overflow the viewport, a dark gray scrollbar is presented (when the user begins scrolling) regardless of the system's current color scheme (dark mode or light mode), but scrollbars on elements with the style "overflow: scroll" use scrollbars that match the system color scheme. When dark mode is enabled, these scrollbars are white and appear invisible on white pages. In short you get this odd matrix of situations: Light mode, body overflow: gray scrollbar Dark mode, body overflow: gray scrollbar Light mode, div overflow: gray scrollbar Dark mode, div overflow: white scrollbar This severely limits accessibility of overflowed elements when the user has selected dark mode on their device. I've attached a couple screenshots in a zip file to demonstrate the issue. files -------- body-scroll-white.jpg: Demonstrates the gray scrollbar on body on a white background even when dark mode is enabled div-scroll-white.jpg: Demonstrates how you can't see the scrollbar on a div with a white background when dark mode is enabled div-scroll-gray.jpg: Demonstrates that the white scrollbar is present and visible on a gray-backgrounded div when dark mode is enabled. Note: This behavior is not present on macOS 10.15.16/Safari 13.1.2