Description

When Real-Time Collaboration is enabled (wp_collaboration_enabled = true), persistCRDTDoc in @wordpress/core-data sends the entire edited entity record back to the server on page load. This causes 400 errors when any field in the record doesn't pass strict REST schema validation — even if the post is perfectly valid and functional.

The issue is in packages/core-data/src/entities.js (built as build/scripts/core-data/index.js around line 5908):

persistCRDTDoc: () => {
  resolveSelect2.getEditedEntityRecord(kind, name, key).then((editedRecord) => {
    const { meta, status } = editedRecord;
    if ("auto-draft" === status || !meta) {
      return;
    }
    dispatch3.saveEntityRecord(
      kind,
      name,
      editedRecord  // ← sends the ENTIRE record
    );
  });
},

saveEntityRecord with a full record hits the non-autosave path, which sends everything as PUT /wp/v2/posts/{id} — including readonly fields, computed fields, and values that the REST API returns on GET but rejects on write.

Step-by-step reproduction instructions

1. Enable Real-Time Collaboration (Settings → Writing → "Enable real-time collaboration", or set wp_collaboration_enabled to 1)
2. In Settings → Discussion, uncheck "Allow link notifications from other blogs (pingbacks and trackbacks) on new posts" and save
3. Create a new post and publish it
4. Open that post in the block editor
5. Open browser DevTools → Network tab
6. Observe a POST /wp-json/wp/v2/posts/{id}?_locale=user request returning 400 Bad Request

The error response:

{
    "code": "rest_invalid_param",
    "message": "Invalid parameter(s): ping_status",
    "data": {
        "status": 400,
        "params": {
            "ping_status": "ping_status is not one of open and closed."
        }
    }
}

This happens because:

• WordPress core saves default_ping_status as "" (empty string) when the checkbox is unchecked (see related Core ticket below)
• The REST API returns ping_status: "" on GET
• persistCRDTDoc sends it back on POST
• REST schema validation rejects "" because the enum is ["open", "closed"]

Why this is a Gutenberg bug (independent of the Core data issue)

persistCRDTDoc only needs to persist meta._crdt_document. Sending the entire entity record is:

• Wasteful — unnecessary data over the wire
• Fragile — any plugin registering a REST field with a schema mismatch (e.g. Co-Authors Plus returns objects where taxonomy schema expects integers) will also cause 400 errors
• Incorrect — readonly fields like guid, generated_slug, class_list should never be sent back to the server

The autosave path in saveEntityRecord already filters to just title, excerpt, content, meta — persistCRDTDoc should do the same, or better yet, only send { meta: { _crdt_document: value } }.

Related

• WordPress Core: default_ping_status saves as empty string when unchecked (Trac #51842, closed as worksforme in 2024 — this issue now provides a clear reproduction path)
• Co-Authors Plus #1217 — similar REST field schema collision exposed by the same round-trip behavior

Environment info

• WordPress 6.9.4
• Gutenberg 22.8.2
• PHP 8.4
• MariaDB (default NOT NULL VARCHAR behavior converts NULL → empty string)

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure