Brightness control in Steam Gamescope session non-functional

[HoodedDeath]

Any attempt to adjust screen brightness within the Game Mode session results in the error <USERNAME> : a password is required ; PWD=/home/<USERNAME>/.local/share/Steam ; USER=root ; COMMAND=/usr/sbin/tee /sys/class/backlight/amdgpu_bl0/brightness being logged in the system journal, potentially an overwhelming number of times as the brightness adjustment attempts to smoothly transition brightness. Will need to take a look at SteamOS proper.

Assumed possible solutions:

1. Drop-in for sudoers to allow password-less use of sudo tee /sys/class/backlight/amdgpu_bl0/brightness
2. Udev rule to allow a group to write to /sys/class/backlight/amdgpu_bl0/brightness, possibly video group. Unsure if this would result to functional backlight control or if the session is always going to attempt to use sudo