You may recall that shortly after Valve's Steam Deck announcement, ProtonDB discovered some of Steam's most popular games wouldn't work on the upcoming handheld. Previously, Easy Anti-Cheat Support was only available on Windows, causing problems for the Linux-based SteamOS.
However, that appears to have been resolved, thanks to Epic Games. Having bought Easy Anti-Cheat in 2018, they've announced that support is now added for Linux, Mac OS and most crucially, Wine and Proton, the compatibility layers used in Linux to run Windows applications.
Steam Deck Resolves Compatibility Issue By Implementing Easy Anti-Cheat Support
Considering Proton is what Valve's used to make their Steam library playable on Steam Deck, that'll come as a relief to those buying the upcoming device. As such, games supporting EAC like Apex Legends, Dead By Daylight, Fall Guys, Halo: The Master Chief Collection, Knockout City and more are in the clear.
Elsewhere with Steam, we've recently seen a patent suggest that Valve are potentially looking to let players play games as they download them, similar to PS4 and Xbox One. Whatever happens next for the PC giants, we'll keep you informed with further details.