Data of Fields within Unnamed Group Is Lost On Localized Publish

[wp99cp]

Describe the Bug

While playing around with the new localizeStatus in payload 3.76.1, I found that any field data within an unnamed group is lost while publishing in a specific locale.

Fields within groups with a name property work as expected. However, when the group is unnamed (used purely for UI organisation), the data does not persist upon publishing.

Link to the code that reproduces this issue

https://github.com/wp99cp/payload-unnamed-group-bug

Reproduction Steps

1. Create a new project based on pnpx create-payload-app@latest -t blank.

2. Enable the localizeStatus feature flag in the payload-config.ts according to step 1 of Status Localisation documentation.

3. Add the following collection:

   import type { CollectionConfig } from 'payload'
   
   export const TestCollection: CollectionConfig = {
     slug: 'test-collection',
     fields: [
       { type: 'text',  name: 'textFieldRoot' },
       { type: 'text',  name: 'textFieldRootLocalized',  localized: true },
   
       // BUG: Data in these fields is lost on publishing in a single locale
       {
         type: 'group',
         // No 'name' property here
         fields: [
           { type: 'text', name: 'textFieldNested' },
           { type: 'text', name: 'textFieldNestedLocalized', localized: true },
         ],
       },
   
     ],
     versions: {
       maxPerDoc: 100,
       drafts: { localizeStatus: true, autosave: { interval: 1000 } },
     },
   }

4. Set up your environment:

   • Copy .env.example to .env
   • Start MongoDB locally: docker compose up --scale payload=0
   • Start the project: pnpm dev

5. Create a new element of the Test Collection type and publish it in a single locale:

Expected Behavior

Data in fields nested within an unnamed group should persist and be saved correctly when publishing a document, as with fields in named groups.

Recordings

Screencast.from.2026-02-16.16-12-20.webm

Which area(s) are affected?

area: core

Environment Info

Binaries:
  Node: 24.11.1
  npm: 11.6.2
  Yarn: 1.22.22
  pnpm: 10.29.3
Relevant Packages:
  payload: 3.76.1
  next: 15.4.11
  @payloadcms/db-mongodb: 3.76.1
  @payloadcms/next/utilities: 3.76.1
  @payloadcms/richtext-lexical: 3.76.1
  @payloadcms/ui/shared: 3.76.1
  react: 19.2.1
  react-dom: 19.2.1
Operating System:
  Platform: linux
  Arch: x64
  Version: #20-Ubuntu SMP PREEMPT_DYNAMIC Mon Jan 19 08:17:52 UTC 2026
  Available memory (MB): 63720
  Available CPU cores: 16