The GitHub Twilight Theme, created by @miksago, provides a dark mode for GitHub, enhancing user experience by reducing eye strain during code review and navigation. The theme requires the use of Firefox along with extensions like Stylish and Greasemonkey to be implemented effectively. Developed by Chris Wanstrath, also known as @defunkt, this theme offers a visually appealing alternative to the traditional GitHub interface, catering to users who prefer darker color schemes.