Custom Slot Highlight

Custom Slot Highlight is a lightweight client-side NeoForge mod for Minecraft 1.21.1.

It replaces the vanilla white inventory and container slot highlight with a configurable in-game overlay. The mod targets Minecraft's shared `AbstractContainerScreen#renderSlotHighlight` path, so it works with vanilla containers and modded containers that inherit the standard Minecraft container screen behavior.

Features:

- Replace the vanilla white slot highlight with a custom overlay.
- Hide the vanilla highlight entirely.
- Restore the vanilla highlight without uninstalling the mod.
- Toggle fill and outline rendering independently.
- Choose built-in color presets from the in-game config screen.
- Configure the mod from `Mods -> Custom Slot Highlight -> Config`.
- No PNG inventory texture replacement.
- No screen rewrites.

Compatibility:

- Minecraft 1.21.1
- NeoForge 21.1.228 or newer on the 1.21.1 line
- Client-side only