OptiFine HD (1.21.2, 1.21.1) is a mod that helps you to adjust Minecraft effectively. It makes Minecraft run more smoothly and use less resources. Besides, it enables you to run resource (texture) pack HD without installing more other mods. Usually it can double or triple your FPS. All in all the mod is a performance related tool that can provide a large FPS boost.
Source: OptiFine HD (1.21.2, 1.21.1)
Check Out: Minecraft Mods
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