OptiFine 1.21.8_HD_U_J6_pre13

 - 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 58.0.3
(03.08.2025)