The problem occurs also in 1.20.1 Forge, but with an "Error executing task on client" instead. I have "Sinytra Connector" installed. On 1.21.5 Fabric, there is no problem. When this happens, the chat message before the death screen appears gets sent, with an extra dash added.
Without Network protocol fix mod, I get kicked with a Network Protocol error when on LAN. Also, both of these issues are caused by a Null Pointer Exception/Screen cannot be null in a "Client Bound Player Combat Kill Packet".
https://mclo.gs/gdftLeY Affected log file https://mclo.gs/lJ3KawM Affected debug file https://imgur.com/a/FtEDXng Affected death screen
I have 200 mods that add new weapons, increase the game’s difficulty… The issue doesn’t happen 100% of the time, but randomly. It is hard to reproduce. Game rule "Show death messages" is enabled. 1.21.1 Neoforge