9to5Mac is brought to you by CleanMyMac by MacPaw . With the release of macOS 27 Golden Gate, use CleanMyMac first to free up space, optimize your system, and ensure your new Mac runs at 100% on day one. Learn more . macOS 27 Golden Gate is a huge upgrade over macOS 26 Tahoe, and not just because of the smarter design decisions. Just like iOS 27 for iPhone, the Mac adds a Liquid Glass appearance s