Is It On Game Pass is a Firefox extension designed for PC gamers looking to optimize their spending on games. This subscription-based tool allows users to see which Steam games are included in their Xbox Game Pass subscription, preventing accidental purchases of titles that are already available. With features like real-time Game Pass availability indicators, it enhances the shopping experience by providing clarity and convenience while browsing Steam.

The extension integrates seamlessly with Steam, displaying visual indicators such as 'Available', 'Coming Soon', and 'Leaving Soon' directly on game pages. Additionally, it offers price comparisons with retail and keyshop deals from GG.deals, making it easier to find the best prices. It works across various pages including store listings, search results, wishlists, and sales, all while maintaining a clean and unobtrusive design that complements Steam's interface.