- Loaders
- FabricNeoForgeForge
- Downloads on Modrinth
- 1.7M
- Followers on Modrinth
- 54
- versions
- 9
- Updated
- October 5, 2026Oct 5
- Published
- in 2023
At a glance
Works both in the game and on the server — install where you need it
Unsafe World Random Access Detector
This is a mod that detects unsafe off-thread world random access, helping to find causes of "Accessing LegacyRandomSource from multiple threads" crash.
This is useful for finding the cause of mysterious crashes with Accessing LegacyRandomSource from multiple threads.
This is not a fix for the issue, but it will help you find the cause of the issue.
Note: If you are already using C2ME, this mod is not needed (but won't crash if used together anyway).
FAQ
How to install Unsafe World Random Access Detector?
Install Fabric for your Minecraft version, download Unsafe World Random Access Detector for the same version and loader, put the file into the mods folder and launch the game with the loader profile.
Which Minecraft versions does Unsafe World Random Access Detector support?
Unsafe World Random Access Detector has builds for Minecraft 1.19–26.3.
Is Unsafe World Random Access Detector needed on the server?
Works on either side — install it in the game, on the server, or both
