Jo0001

No you are not. Please download them from https://ci.viaversion.com/job/ViaVersion/lastSuccessfulBuild/artifact/build/libs/ViaVersion-4.3.2-SNAPSHOT.jar and https://ci.viaversion.com/view/ViaBackwards/job/ViaBackwards/lastSuccessfulBuild/artifact/build/libs/ViaBackwards-4.3.1-SNAPSHOT.jar Also this issue is caused by a plugin sending invalid data. To find out which do a binary plugin...

1.13.2, 1.14.4 and 1.15.2 are also affected. However just following a player with a warped_fungus_on_a_stick in the hand works fine https://dump.viaversion.com/da242357a336ccdd033f17bfe31672a965de79c733b736c2cc2f981e95deb741

Works fine for me with the latest Via* 

> I tested 1.8.8 myself and it seems 1.8.9 is the issue. 1.8.9 also works fine for me. You have to try which of your plugins cause it

Crash message: `java.lang.ArrayIndexOutOfBoundsException: 4` (Latest Paper 1.16.5 + Via ci builds)

ViaVersion/Backwards 4.0.1 and ViaRewind 2.0.1 are outdated. Please try it with the latest Via* plugins from Spigot (#links on Discord)

Works fine for me using the latest paper 1.16.5. In the stacktrace is a bossbar mentioned so you have probably some invalid bossbar (from the LobbySystem plugin)

Its working fine for me with just Via* installed. The only differences between your and my setup are the server software (I used paper) and the Java version (I use...

Do you use a proxy (like Bungee) ?

Next time please follow the template. To fix your issue please also install ViaRewindLegacy-Support.