Mod conflicts

Crash When Opening Inventory: IllegalArgumentException: Duplicate delegates

What the log looks like

java\.lang\.IllegalArgumentException: Duplicate delegates
Duplicate delegates[\r\n]+\s+at net\.minecraft\.class_4720\$class_4589\.<init>

How to fix it

  1. Update Iris Shaders (Fabric/Quilt) or Oculus (Forge/NeoForge) to the latest release for your Minecraft version—for instance, updating from Iris 1.4.4 to 1.4.5+ directly resolves the 1.19.2 inventory crash.
  2. Update companion rendering and inventory mods such as Sodium (or Embeddium) and Just Enough Items (JEI) so their item overlay renderers match your updated shader mod.
  3. If you are stuck on a modpack version you cannot immediately update, avoid opening your inventory while taking damage or while holding/wearing enchanted gear (like enchanted armor or banner shields) until the shader mod is updated.
LoadersFabric, Quilt, Forge, Neoforge
SeverityStops the game
CategoryMod conflicts

Check your own log

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