Your system information

• Steam client version (build number or date): Apr 12/2021
• Distribution (e.g. Ubuntu): Arch (Gentoo and Fedora too)
• Opted into Steam client beta?: Yes
• Have you checked for system updates?: Yes

Please describe your issue in as much detail as possible:

When Steam (both native and flatpak versions) starts, my Xbox one S controller is detected as expected and can be configured, but when I start games, the controller is inoperable within the game, but I can open it Steam-overlay without problems (which also has something wrong, I'll explain later).
Evaluating the program outputs when I execute via terminal, the following information appears:

Couldn't initialize virtual gamepad: Couldn't open /dev/uinput for writing

So, the first thing I did was to load the uinput module and give the appropriate permissions (my user is in the input group) :

sudo modprobe -v uinput
sudo chmod +0666 / dev / uinput

After executing these commands, I tried again, and saw that the problem persisted, but out of curiosity I started to tweak my settings and saw that Steam-Overlay was disabled, so I enabled it and restarted steam and ran the BroForce game, and the controller worked normally (but it was still necessary to load the uinput module and give the permissions). I repeated the same steps a few times and got the same result.

here the terminal outputs with Steam-overlay enabled + uinput and chmod and here Steam-overlay disabled + uinput and chmod

Steps for reproducing this issue:

1. Open Steam
2. Start the game
3. Try to use the controller in the game, executing some commands