Gamma not changeable on GLESv1

[Truedufis20]

Describe the bug
The settings for gamma is greyed out when the graphics library is set to GLESv1

To Reproduce
Steps to reproduce the behavior:

1. Open the launcher
2. Change the graphics library to GLESv1
3. Scroll down to 'gamma'
4. It's greyed out

Expected behavior
Gamma changeable for all graphics libraries

Screenshots
If applicable, add screenshots to help explain your problem.

Smartphone (please complete the following information):

• Device: Galaxy A51
• OS: Android 11
• Version: both stable 0.46 and nightly 0.47
• App source: Google Play store

Additional context
The game is WAY to dark on GLESv1 and runs too slow on GLESv2. I have no idea if it's something that's tied to GLESv2, so any advice would be appreciated

[xyzz]

It's only supported on GLESv2 because it uses shaders to change gamma, not sure there's a way to do that on GLESv1.

[Truedufis20]

Is there any way to change the brightness in GLESv1? I've tried changing the lighting in the nightly between legacy and shader compatible, but the ground is black on shader compatible in exteriors and interiors are too dark on legacy.