Sodium Crash: ClassNotFoundException net/minecraft/class_8819 (Wrong Minecraft Version)

What the log looks like

java\.lang\.ClassNotFoundException: net/minecraft/class_8819\)
@Mixin target net\.minecraft\.class_8819 was not found \S+:core\.gui\.LevelLoadStatusManagerMixin from mod [\w-]+

How to fix it

1. Check the top of your `latest.log` to confirm the exact Minecraft version your profile is launching (for example, a snapshot like `25w31a` or an older release like `1.20.2`).
2. Delete the mismatched `sodium-fabric` JAR from your `mods` folder; release builds of Sodium do not work on Minecraft snapshots or across incompatible minor versions.
3. If you are playing a standard release, download the Sodium version from Modrinth or CurseForge that explicitly lists your exact Minecraft version in its filename and game-version filter.
4. If you are trying to play a Minecraft snapshot, either remove Sodium until an official snapshot-compatible build is released or switch your launcher instance back to the stable Minecraft version your mods were built for.
5. Verify that standalone `fabric-api` and other installed mods in your `mods` folder also match your exact Minecraft version so no other outdated mixins remain.

Check your own log