[BUG] AdvancedChatBox: Game crashes when entering JSON text into a command

[floral-qua-floral]

Describe the bug
When I type in some JSON text in a command that accepts it (such as /tellraw or /title), the game will crash as soon as it becomes valid. It doesn't crash while the JSON is invalid, such as when it's missing a quotation mark or curly bracket. It also doesn't crash if you just start typing JSON somewhere it doesn't belong, such as a chat message or a command that doesn't accept JSON (such as /tp). When you press the last key that would make the JSON valid, the game will crash before the character can appear.

Minecraft Info
Minecraft information:

• Minecraft 1.18.1
• Fabric Loader 0.12.12-1.18.1
• AdvancedChatCore 1.3.2
• AdvancedChatBox 1.1.1
• Fabric API 0.45.0
• MaLiLib 1.18.0-0.10.0-dev.26
  No other mods are installed. Of note is that removing AdvancedChatBox makes the issue no longer occur.

To Reproduce

1. Open chat
2. Type /tellraw @s {"text":""
3. Add the closing curly bracket. The game will crash
4. Re-enter game and open chat
5. Type {"text":"JSON"}
6. Move the text cursor back to the start of the message and type /title @s title . The game will crash

Expected behavior
I'd assume some sort of JSON-specific syntax highlighting is supposed to show up?

Additional context
Crash report:
crash-2021-12-28_14.35.16-client.txt
Launcher warning:

    The game crashed whilst rendering screen
    Error: java.lang.StringIndexOutOfBoundsException: begin 12, end 24, length 23
    Exit Code: -1

[John-Paul-R]

Can also reliably reproduce this (e.g. /tellraw @p "testing" -> crash).

Originally reported to me through this issue John-Paul-R/Essential-Commands#91