Wrong Minecraft version

ClassNotFoundException: net/minecraft/class_3950 (Fabric API / Mod Version Mismatch)

What the log looks like

java\.lang\.ClassNotFoundException: net/minecraft/class_3950\)
Error loading class: net/minecraft/class_3950[\s\S]{0,250}Mixin apply for mod fabric-resource-loader-v0 failed

How to fix it

  1. Check your Minecraft profile version and verify whether you are running a snapshot or a newer release (such as 25w31a or 1.21.9+) than your mods were built for.
  2. Open your `mods` folder and remove outdated mods built for older game versions (for example, `sodium-fabric` for `mc1.21.6`), because Sodium does not support snapshots and bundles older Fabric API modules internally.
  3. Install the exact version of Fabric API made for your specific Minecraft version, and either wait for your other mods to update or switch your Minecraft installation back to a supported release.
LoadersFabric, Quilt
SeverityStops the game
CategoryWrong Minecraft version

Check your own log

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