The fabric mod does not work correctly when connected to the Velocity lobby. Having a mod on the client does not allow you to connect to the server. For example, one of the log lines: [00:12:00] [Netty Client IO #1/WARN]: Incorrect key serverConfig.claims.adminModePermission was corrected from null to its default, xaero.pac_admin_mode.

Velocity: 3.3.0-SNAPSHOT-390
Fabric API: 0.92.1

Full client log: 2024-05-22-1.log

These warning are completely normal and shouldn't break anything. Not sure why you're even seeing them on the client side though. Can I see the server log?

Did you figure it out? @skofqq

I'm probably having the same problem on the default fabric server in version 1.20.1-0.15.11, but the configs are reset every time they load or modified. Players can join the game

So, I found a workaround that can temporary fix this issue, just copy your config inside defaultconfigs folder and it should "force-overwrite" (or whatever that called) configs and load them properly.

It's possible that this issue is related on the forgeconfigapiport library, as I remember.