This Fabric mod for Minecraft 1.21 enables the debug feature renderServerSideHitbox which is present as an unused function in the game's code. Enable hitboxes with F3+B and this mod will show the server-side hitboxes in green in addition to the normal client-side ones in white.
This only works for the integrated server in singleplayer mode.
Usage examples include observing desync after sprint-punching entities or standing on a client-side piston head.
How to Install Entity Desync Viewer (Mod)
Entity Desync Viewer by crazysmc is verified for Fabric across Minecraft versions 1.21, 1.21.1, 1.21.1-rc1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6 (latest release: 1.0.3+1.21.5, file size: 42 KB). Follow the steps below to install it safely from ModCraft.tv:
- Click the Download button above and select your Minecraft version (1.21, 1.21.1, 1.21.1-rc1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6) and platform (Fabric).
- Make sure you have the compatible loader or environment installed for Fabric.
- Move the downloaded Entity Desync Viewer file into your Minecraft
.minecraft/modsfolder and launch the game.