Mixin failures

Harmless Server Warning: ClassNotFoundException net/minecraft/class_906 (Porting Lib)

What it looks like in the log

java.lang.ClassNotFoundException: net/minecraft/class_906)

How to fix it

  1. Ignore this warning if your server starts and runs normally, as Mixin automatically skips the missing rendering class without breaking gameplay.
  2. If your server actually crashed or refuses connections, scroll past the startup `[WARN]` lines to the very bottom of `logs/latest.log` or open the newest file in `crash-reports/` to find the real `[ERROR]` or exception.
  3. If you cannot join a running server (for example, getting a mismatch or disconnect error), check the client's `logs/latest.log` as well as the bottom of the server log right after the connection attempt.
  4. Optionally update Create and any standalone Porting Lib mods to their latest versions for your Minecraft release to reduce startup log warnings.
LoadersFabric, Quilt, Server
SeverityWorth checking
CategoryMixin failures

Check your own log

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