Valve is rolling out an update to its desktop Steam app that replaces the aging Big Picture mode, designed for use on TVs via a gamepad, with the UI for the Steam Deck handheld Linux PC-console gaming machine.
For now, it’s in testing, so only available if you’re running the beta version of the Steam client app (accessed through Settings > Account) and if you add the argument “-gamepadui” (without the quote marks) to the end of the ‘target’ in the shortcut properties for the application. There's a short walkthrough on how to access it on the announcement page.
What you get is, well, the Steam Deck UI. It’s so Steam Deck, in fact, that the banner asking you for feedback asks you to “help improve Steam Deck”. In the library view your games are listed as large tiles horizontally scrolling across the top of the interface, easy to flip through with an analog stick rather than trying to pick a line of text from the usual desktop Steam library view. In the lower part of the UI is a section for news, DLC releases, and info about what your friends are playing.
The store supposedly receives similar treatment, but we couldn't get it to load. It’s still a beta, however, so as Valve points out, there may be a few rough edges. Hopefully this flaw will be patched soon.
The buttons for things like Menu, Select and Back are labelled with Xbox controller prompts, but can also be clicked on with a mouse pointer. There's also a new universal search algorithm, which roots out your search terms from your library, the store, and your friends. A controller configurator makes it easier to set up custom controller schemes and switch between them. There's an updated in-game overlay accessed using the central button on the controller that goes by various names depending on the manufacturer, and the system and quick access menus have been polished too.