Mod conflicts

Lithium and OptiFabric World Load Crash (IllegalAccessError: field_18247)

What the log looks like

java\.lang\.IllegalAccessError: tried to access field net\.minecraft\.class_3898\$class_3208\.field_18247 from class net\.minecraft\.class_3898

How to fix it

  1. Open your Minecraft game directory and navigate to the mods folder.
  2. Remove both the OptiFine and OptiFabric .jar files so you can keep using Lithium (or remove Lithium if you prefer to keep OptiFine).
  3. If you removed OptiFine and still want client-side rendering performance and shaders on Fabric, install Sodium and Iris Shaders instead, as they are built to work alongside Lithium.
  4. Launch Minecraft and load your single-player world again.
LoadersFabric
SeverityStops the game
CategoryMod conflicts

Check your own log

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