Brightness settings have no effect in Fallout: New Vegas

Hey there, this is not Lutris’s fault, but I thought maybe someone smart could offer some advice. I am running Fallout New Vegas (the New California mod to be specific) with Wine tkg4.2 64-bit and DXVK .96 with the WineSteam runner.
I have also tried playing this game with Proton through Linux Steam, but either way, my brightness settings in-game don’t actually do anything. I noticed this when playing Enclave too.
If I adjust the Gamma setting in Nvidia settings, the game looks fine, but I was just hoping to not have to change my desktop gamma before/after every time I play a Wine game.
Does anyone know of a fix or a workaround?

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-+ssssssssssssssssssyyssss± OS: Ubuntu 18.04.2 LTS x86_64
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ossyNMMMNyMMhsssssssssssssshmmmhssssssso DE: KDE
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