Registry error on 1.21.5

[HumanDuck23]

[x] The FAQ doesn't contain a resolution to my issue

Versions

• minecraft-protocol: 1.60.0
• server: vanilla/spigot/paper 1.21.5
• node: 24.5.0

Detailed description of a problem

Joining this simple server with a 1.21.5 client (other versions lower too) causes a registry loading error on the client. It appears NMP doesn't send registry packets for modern clients or sends them incorrectly.

Current code

const mc = require("minecraft-protocol")

const server = mc.createServer({
  host: "127.0.0.1",
  port: 25565,
  version: "1.21.5",
  "online-mode": false,
})

Expected behavior

The client to get past the configuration phase

Additional context

This is the error log https://pastebin.com/Qg4sqduD