Zen Browser — Twilight is a version of the Zen Browser, a web browser based on the Firefox codebase that focuses on privacy, customizability, and a streamlined browsing experience. Twilight refers to an experimental or pre-release build of the browser, offering the newest features before they are included in the stable version, but it may be less stable and contain more unfinished elements. The browser displays web pages, manages tabs, and blocks trackers by default, and it runs on desktop platforms like Windows, macOS, and Linux. Twilight is mainly intended for testing and early access to updates rather than everyday use by all users.