I don't know of a good way of doing that before buying, only after. Outside of aforeposted lists.
Launch exe with Steam not running, see if it works or if it opens Steam automatically
Should say on the store page, shouldn't it? Could've sworn I saw Denuvo specifically listed before unless there's just a gas leak in my house or they changed it or something.
Unfortunately, that popup only lists third party DRM.
All games on Steam use Steams DRM, I would have thought.
They do not have to. FTL is one example I know of off the top of my head.
The original Kerbal Space Program is another. You can uninstall Steam completely but still launch the game just fine. It's actually pretty handy if you want separate mod loadouts, just copy the whole directory.
Selaco doesn't.
Steam is a video game digital distribution service by Valve.
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Useful tools:
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Issue tracker for Linux version of Steam