• [ X ] This issue is not solved in a development build

Describe the bug
When i put the new version 5.2.0 instead of 5.1.0 i can't connect on my server, the server shut down with this error
Error : https://mclo.gs/0aHkbzQ

To Reproduce
Put the new jar in paper or spigot 1.8 and connect in 1.8

Expected behavior
Can play and connect to my server

Screenshots

Version Info
https://mclo.gs/j2VJLXy

Additional context