Server setup

Folia: Accessing entity state off owning region's thread

What the log looks like

java\.lang\.IllegalStateException: Accessing entity state off owning region's thread
failed main thread check: Accessing entity state off owning region's thread

How to fix it

  1. Check the warning line right above the error (for example, 'Global task for <Plugin>' or 'Location task for <Plugin>') and scan the stack trace for any '.jar' file other than Folia to identify the responsible plugin.
  2. Update that plugin to its newest Folia-compatible release, as plugins like Towny and tab/hologram managers frequently fix region-scheduler bugs across updates.
  3. If no plugin JAR appears in the stack trace (such as crashes involving CraftTextDisplay or vehicle dismounts on player disconnect), update your Folia server JAR to the latest build and test if a plugin attached a hologram or nametag passenger to players.
  4. If an updated plugin continues throwing this error, remove it and send the stack trace to the plugin developer so they can move the logic onto Entity#getScheduler() instead of global or location schedulers.
  5. If multiple plugins on your server cannot run safely under Folia's region threading rules, migrate the server from Folia back to standard Paper.
LoadersServer
SeverityBreaks something
CategoryServer setup

Check your own log

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