String Duper Restorer

还原 1.21.2+ 被修复的经典刷线机漏洞

English Description

Introduction

This mod reintroduces the string duplication exploit that Mojang patched in Minecraft 1.21.10 and above.

The string duper is a classic exploit that has existed since Java 1.8, allowing players to duplicate String using Tripwire Hooks and water mechanics. It has been widely used by the technical community for:

Obtaining massive amounts of string to craft wool as a renewable fuel source.
Trading with villagers for emeralds, which can then be exchanged for diamond gear and other valuable items.
Quickly accumulating resources in skyblock, hardcore survival, or limited-resource maps.

Note: This mod is only compatible with Minecraft Java Edition 1.21.10+ and requires Fabric. It does not work on vanilla servers unless the mod is installed on the server side as well.

Features

Restores the duplication behavior of tripwire hooks and water that was removed by Mojang (patches MC-59471 and MC-129055).
Does exactly one thing – no extra features, no bloat.
Works in single-player and on servers (server‑side installation is enough for all players).

Supported Versions

Minecraft 1.21.10, 1.21.11, 26.1, and any later 26.x releases.
Mod Loader: Fabric (API required).

Installation

Download the mod jar file for your Minecraft version.
Place it in your .minecraft/mods folder (or the mods folder on your server).
Launch the game or server – the string duper will work just like it did before 1.21.2.

Related Bugs

Bug ID	Description
MC-59471	Main duplication exploit using tripwire hooks.
MC-129055	Related inconsistency in tripwire hook states.

Both were fixed in 1.21.2+; this mod reverts those fixes.

License

This mod is licensed under the MIT License – you are free to use, modify, and distribute it, as long as you retain the copyright notice.

Disclaimer

This mod is not affiliated with Mojang Studios. Use it at your own risk. The author is not responsible for any world corruption, server crashes, or other issues caused by this mod.

String-Duplication