OptiFine 1.21.8_HD_U_J6_pre16

 - fixed screenshot size (#7936)
 - fixed shaders lightmap and custom lightmap affecting GUI (#7975)
 - fixed shaders hand depth (#7974)
 - updated shaders screen to show changed options
 - fixed shaders projection matrix (#7977)
 - fixed shaders render quality (#7987)
 - fixed options saving with Forge
 - fixed end portal rendering with shaders
 - fixed custom lightmap texture in shaders properties (#7961)
 - fixed chest rendering in GUI with shaders (#7967)
 - fixed shadow pass uniforms delayed by one frame (#5134)
 - fixed shadow frustum culling (#7966)
 - fixed hand rendering with shaders (#7965)
 - fixed crash in GUI rendering with shaders
 - fixed crash with shaders on Mac
 - fixed FXAA shaders
 - fixed shaders
 - fixed lava with render regions (#7955)
 - fixed biome colors with smooth lighting (#7952)
 - updated to 1.21.8
 - compatible with Forge 58.1.0
(29.08.2025)