StackCluster Optimizer

A lightweight client-side FPS optimization mod for Minecraft 1.21.11 (Fabric).
When large amounts of the same item are dropped on the ground in a pile — like after a mob farm, bulk crafting, or a death — Minecraft renders every single item entity individually, which can tank your FPS. StackCluster fixes this by detecting clusters of the same item and hiding a configurable percentage of them visually. The items still exist and can be picked up normally — they're just not rendered.
Features:

Fully client-side — works on any server, no server-side install needed
Configurable cluster radius (how far to search for same-type items)
Configurable minimum cluster size (how many items trigger culling)
Configurable cull percentage (how many items in a cluster to hide)
Master on/off toggle
In-game config screen via ModMenu + Cloth Config

Requirements:

Fabric Loader 0.19+

Fabric API

Cloth Config

ModMenu (optional, for in-game config screen)

Performance tip: The default settings (3 block radius, min 3 items, 90% culled) are conservative. For mob farms or bulk item drops, try radius 5-6 and 95% cull for maximum FPS gains.