C12PacketUpdateSign should only send plain Strings

Relates to:

• MC-94906

Introduction

This is based on Mincraft 1.8 (decompiled with MCP) and might not be the case anymore.

The bug

The C12PacketUpdateSign has as parameter an array of IChatComponent s that are sent to the server. In 1.8 the server simply set them as the sign IChatComponent of the sign it stored. This means that the player could send null as IChatComponent for one line. In 1.8 this does not create any problems, but in the latest snapshots it could.

Additionally this means the player can determine the ChatStyle of the lines. This does not only mean the player can use colors and formatting styles, but can also set events. Based on this the player can for example send the following packet once he edited a sign:

Removed this

This would make the player to an operation once he right clicks the sign.