Cloudflare Worker "Failed to publish diagnostics channel message" Error

[ThomasAWood]

Describe the Bug

The Cloudflare template shows lots diagnostic channels errors in the Cloudflare worker logs.
Error message: "Failed to publish diagnostic channel message: "

Cloudflare Workers support Diagnostic Channels which are called in Payload by the undici library. However, I'm not sure that opennextjs-cloudflare supports the use of diagnostics channels or not.

Link to the code that reproduces this issue

https://github.com/payloadcms/payload/tree/main/templates/with-cloudflare-d1

Reproduction Steps

1. Use Payload's 1 click Cloudflare deployment
2. Activate Observability for the Cloudflare Worker running Payload CMS
3. Perform some action on the deployed CMS
4. Look in the observability logs and you'll see the "Failed to publish diagnostics channel message"

Which area(s) are affected?

Not sure

Environment Info

Binaries:
  Node: 22.20.0
  npm: 10.9.3
  Yarn: N/A
  pnpm: 10.22.0
Relevant Packages:
  payload: 3.64.0
Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 25.1.0: Mon Oct 20 19:33:00 PDT 2025; root:xnu-12377.41.6~2/RELEASE_ARM64_T6020
  Available memory (MB): 32768
  Available CPU cores: 12