There was a Written Book in a chest that had
alot of weird scribbles in the title (Example: "Æ*''£#/&ø=/(&¤").

What I expected to happen was...
I expected there to just a bunch of random scribbling
in the book.

What actually happened was...
The game disconected, and gave me the
weirdest error report that i have ever seen. "InternalException: io.netty.handler.codec.decoderexception:java.lang.IndexOutOfBoundsException: readerindex(1256) + lenght(1) exceeds writerIndex(1256): UnpooledHeapByteBuf(ridx: 1256, widx: 1256, cap: 1256/1256"

Here's how it happend:
1. I Logged into the main server (multi-server server).
2. Then, i went into the Admin-Builds server.
3. After poking around, i found the book, opened the weird book, and then the game disconected.

After that first disconection, i have since been unable to reconnect
to that server. If i try to reconnect, it gives me the same error again.

It's possible that that Written Book was from the previous Minecraft version: 1.7.10

It's also possible that there was an error within the server's plugin-files
(The server also uses Spigot)