Controller support doesn't work properly on the Linux build. The DPad doesn't work, L2 (LT) is set as a movement axis (accidentally pressing it makes it the only accepted way of moving), and somehow Pause ends up being mapped to L3 (Left Stick Click).
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I'm using SteamOS on a Steam Deck. Both the Steam Deck's internal controller, and an external bluetooth controller are affected. (I don't have the game on Steam, I got it here from a bundle.)
I've run it from the desktop and in Steam using the Steam Linux Runtime, and both result in the same problem with the controls.
Something strange I noticed is that the improperly mapped inputs seem to align with what happens when I run a game designed for DInput controllers while using an XInput controller, with the exception that the face buttons (ABXY) all work correctly.
I don't have a PlayStation controller, but I think that if I tried to use one, it would work correctly.