Millenium.exe

: Ability to track playtime for non-Steam games added to the library.

As a modding tool, Millennium primarily focuses on personalizing and extending the Steam interface:

: Install custom CSS-based themes to change the visual appearance of the Steam library, friends list, and store. MILLENIUM.exe

: Displaying real-time SteamDB data directly on game pages.

: It is designed to be lightweight, hooking into Steam's existing Chromium-based UI without significant resource overhead. Potential Contextual Confusion : Ability to track playtime for non-Steam games

Depending on where you encountered the file, it may refer to older or niche software rather than the modern Steam mod:

: Adds new features through community-developed plugins. Examples include: MILLENIUM.exe

: Restoring navigation history for the internal Steam browser.