Description
When using Multiconnect together with Krypton, sending too long messages to the chat leads to disconnection from the server with the error "The string is too big": https://youtu.be/vSiVAoM5Hew

Additional
Multiconnect#376
latest.log

https://github.com/astei/krypton/blob/master/src/main/java/me/steinborn/krypton/mixin/shared/network/microopt/PacketByteBufMixin.java#L44
Vanilla uses the amount of UTF-16 char (2 bytes) used by string, not the UTF-8 byte amount
This is getting triggered when non ASCII charset is used on your chat message

Also probably it happens without multiconnect

Fixed with 8d957c9