Describe the bug, provide any errors
Internal Exception: io.netty.handler.codec.DecoderException:
io.netty.util.IllegalReferenceCountException: refCnt: 0

How can we reproduce it?
Steps to reproduce the behavior:

1. Make a server on aternos
2. Add viaversion, viabackwards, viarewind, multiverse, and screamingbedwars
3. Setup a bedwars game
4. Join it using /bw join on 1.8 or 1.7
5. It will kick you out with an error

Expected behaviour
Doesnt kick me out and actually lets me play the game

Screenshots

ViaVersion Dump:

• Type /viaversion dump, and put the link here.
  https://dump.viaversion.com/4ca8f363b50df0c740c0c9dd637b691bd2f97d215798c54f5cde2f6c04644c1b

Additional server info
Do you use a proxy (eg. BungeeCord)? What software do you use and what plugins?
No. I'm using viaversion, viabackwards, viarewind, multiverse, and screamingbedwars

Checklist (mark with [X] to check)

• I have included a ViaVersion dump
• If applicable, I have included a paste (not a screenshot) of the error
• [] I have tried a build from https://ci.viaversion.com/ and the issue still persists
• I have looked at https://www.spigotmc.org/resources/viarewind-legacy-support.52924/ and it does not offer a fix for my problem

IMPORTANT: Follow the Checklist or we can't reproduce your issue and your issue will be close

I have fixed this issue, it was a problem with bossbars
Disabling the bossbars in the ScreamingBedwars config.yml fixed it

bossbar:
  use-xp-bar: false
  lobby:
    enable: false
    color: YELLOW
    style: SEGMENTED_20
  game:
    enable: false
    color: GREEN
    style: SEGMENTED_20