Core Data: Keep read-only taxonomy fields out of collaborative edits

[ciampo]

Follow-up to #79908. Related to #78594. Found through the failing Playwright job on #84584.

What?

Keep read-only taxonomy term fields out of collaborative edits so stale counts and links do not mark unchanged categories as dirty.

Why?

After another post is published, REST can return a category count of 1 while its shared document still contains 0. Applying that stale count as an edit changes the pre-publish button to "Save" and can trigger an unsaved-changes warning.

Taxonomy record syncing was introduced in #74665. The comparison added in #79908 excludes equal values, but stale read-only values still differ and reach the store as edits. The original test passes on a fresh site; changing the count between tabs reproduces the failure on trunk.

How?

Use a taxonomy-specific sync config that excludes id, count, link, taxonomy, _links, and _embedded when writing and reading shared documents. Reading also filters documents created before this fix. Editable term fields, plugin fields, and taxonomy assignments continue to sync.

Testing Instructions

1. Enable the real-time collaboration experiment and open a draft post.
2. Open its pre-publish panel to load the default category into sync.
3. Publish another post assigned to that category in another tab.
4. Open the original draft and its pre-publish panel in a second tab.
5. After both tabs exchange sync updates, confirm the category has no unsaved edits and the panel button still says "Publish".

The existing Playwright regression test now performs this sequence automatically.

Verification

• The two new unit cases and the strengthened Playwright test fail without the fix.
• 121 focused unit tests pass with the fix, including stale-document handling and editable/plugin field coverage.
• The Playwright regression test passes three consecutive runs on Chromium.
• The full build, type check, and focused JavaScript lint pass.

Testing Instructions for Keyboard

Follow the same steps using Tab to reach each Publish button and Enter to open the panel. The change does not alter keyboard interaction.

Use of AI Tools

Codex investigated the failure, traced its history, implemented the fix and tests, and ran local verification.

[github-actions]

🤖 PR meta 🤖

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Co-authored-by: ciampo <mciampini@git.wordpress.org>

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📦 Bundle size

Size Change: +50 B (0%)

Total Size: 8.65 MB

📦 View Changed

Filename	Size	Change
build/scripts/core-data/index.min.js	79 kB	+50 B (+0.06%)

_{a6040dc Run}

⚡ Performance

Show the results

Client side metrics exclude the server response time.

front-end-block-theme

Metric	77e7376	trunk	% Change
timeToFirstByte	42.2 ms +13.03% -9.72%	36.7 ms +12.94% -5.04%	14.99%
largestContentfulPaint	72 ms +11.11% -5.56%	68 ms +0% -8.82%	5.88%
lcpMinusTtfb	28.6 ms +22.9% -7.52%	26.55 ms +23.73% -3.39%	7.72%
wpBeforeTemplate	21.81 ms +19.35% -8.62%	19.06 ms +13.8% -2.52%	14.43%
wpTemplate	15.54 ms +12.55% -4.57%	14.42 ms +6.03% -10.54%	7.77%
wpTotal	38.96 ms +10.93% -10.73%	33.48 ms +14.19% -5.59%	16.37%
wpMemoryUsage	7.61 MB +0% -0%	7.57 MB +0% -0%	0.45%
wpDbQueries	17 +0% -0%	17 +0% -0%	0%

front-end-classic-theme

Metric	77e7376	trunk	% Change
timeToFirstByte	33.6 ms +9.37% -3.13%	31.95 ms +8.29% -4.85%	5.16%
largestContentfulPaint	76 ms +10.53% -2.63%	72 ms +5.56% -5.56%	5.56%
lcpMinusTtfb	40.85 ms +14.08% -1.84%	40.05 ms +3.37% -4.49%	2%
wpBeforeTemplate	18.41 ms +10.54% -3.75%	17.37 ms +7.6% -3.68%	5.99%
wpTemplate	12.27 ms +7.82% -3.67%	11.48 ms +4.62% -5.49%	6.88%
wpTotal	30.83 ms +9.83% -4.31%	29.25 ms +8.48% -4.79%	5.4%
wpMemoryUsage	6.27 MB +0% -0%	6.22 MB +0% -0%	0.7%
wpDbQueries	14 +0% -0%	14 +0% -0%	0%

media-processing

Metric	77e7376	trunk	% Change
mediaProcessingJpeg	232.61 ms +6.63% -2.38%	234.41 ms +1.62% -0.89%	-0.77%
mediaProcessingAvif	3788.96 ms +1.37% -0.82%	3749.54 ms +0.56% -1.44%	1.05%
mediaProcessingJpegToAvif	2601.78 ms +0.78% -0.63%	2623.65 ms +0.07% -2.41%	-0.83%

media-upload

Metric	77e7376	trunk	% Change
jpegUploadProcessing	1163.69 ms +21.78% -21.68%	950.66 ms +46.99% -3.83%	22.41%
pngUploadProcessing	167.22 ms +4.3% -1.6%	174.41 ms +2.3% -2.38%	-4.12%
largeJpegUploadProcessing	925.4 ms +51.33% -1.31%	917.66 ms +1.68% -1.35%	0.84%
multipleImageUploadProcessing	1535.78 ms +1.2% -1.78%	1513.56 ms +0.77% -0.88%	1.47%

post-editor

Metric	77e7376	trunk	% Change
serverResponse	412.26 ms +8.64% -5.77%	415.65 ms +2.87% -7.1%	-0.82%
firstPaint	283.47 ms +76.15% -26.98%	274.73 ms +72.16% -13.35%	3.18%
domContentLoaded	1174.04 ms +3.06% -0.3%	1178.15 ms +1.88% -3.84%	-0.35%
loaded	1175.56 ms +3.05% -0.31%	1179.55 ms +1.86% -3.83%	-0.34%
firstContentfulPaint	500.92 ms +7.4% -9.91%	516.47 ms +3.13% -8.42%	-3.01%
firstBlock	3453.39 ms +1.51% -1.27%	3432.8 ms +0.67% -0.64%	0.6%
type	18.73 ms +5.18% -1.23%	19.24 ms +1.61% -1.35%	-2.65%
typeWithoutInspector	19.45 ms +1.03% -3.75%	19.23 ms +1.14% -3.43%	1.14%
typeWithTopToolbar	23.64 ms +3.26% -3.51%	23.38 ms +13.99% -4.75%	1.11%
typeContainer	9.04 ms +6.08% -8.74%	9.74 ms +6.88% -10.88%	-7.19%
focus	122.16 ms +4.46% -3.31%	120.18 ms +3% -4.63%	1.65%
firstFocus	227.97 ms +0% -0%	244.46 ms +0% -0%	-6.75%
selectAll	577.4 ms +3.14% -2.75%	559.54 ms +3.48% -0.71%	3.19%
listViewOpen	79.23 ms +3.53% -4.85%	79.54 ms +5% -6.74%	-0.39%
inserterOpen	40.64 ms +15.97% -3.74%	40.32 ms +12.45% -5.95%	0.79%
inserterHover	13.05 ms +7.2% -6.51%	13.06 ms +8.19% -11.26%	-0.08%
inserterSearch	8.83 ms +1.81% -5.32%	9.19 ms +7.07% -3.16%	-3.92%
loadPatterns	660.52 ms +6.67% -6.35%	670.66 ms +2.24% -5.22%	-1.51%
wpTotal	400.98 ms +8.81% -5.99%	404.53 ms +2.92% -7.29%	-0.88%
wpMemoryUsage	13.29 MB +0% -0%	13.26 MB +0% -0%	0.28%
wpDbQueries	54 +0% -1.85%	54 +0% -1.85%	0%

site-editor

Metric	77e7376	trunk	% Change
serverResponse	488.04 ms +6.48% -3.62%	479.34 ms +3.71% -3.59%	1.81%
firstPaint	278.69 ms +9% -26.18%	247.39 ms +9.82% -8.49%	12.65%
domContentLoaded	1214.15 ms +2.58% -0.34%	1232.31 ms +3.64% -1.53%	-1.47%
loaded	1215.28 ms +2.58% -0.34%	1233.69 ms +3.63% -1.55%	-1.49%
firstContentfulPaint	509.57 ms +3.25% -1.84%	510.75 ms +2.06% -3.63%	-0.23%
firstBlock	4519.84 ms +1.87% -1.14%	4577.45 ms +2.4% -0.83%	-1.26%
type	18.27 ms +4.32% -0.55%	17.98 ms +9.51% -6.23%	1.61%
navigate	111.74 ms +7.92% -0.17%	117.26 ms +1.14% -3.33%	-4.71%
loadPatterns	1219.78 ms +5.88% -2.69%	1166.35 ms +8.78% -8.48%	4.58%
loadPages	996.43 ms +1.98% -1.96%	999.96 ms +2.17% -2.1%	-0.35%
wpTotal	478.12 ms +6.58% -3.58%	469.64 ms +3.88% -3.63%	1.81%
wpMemoryUsage	12.35 MB +0% -0%	12.32 MB +0% -0%	0.3%
wpDbQueries	43 +2.33% -0%	43 +2.33% -0%	0%

_{a6040dc Run}

🏁 Flaky tests

Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

default to a list of pages if there are no menus in /test/e2e/specs/editor/blocks/navigation.spec.js, passed after 1 failed attempt.

Error: expect(locator).toBeVisible() failed

Locator: locator('[name="editor-canvas"]').contentFrame().getByRole('document', { name: 'Block: Page List' })
Expected: visible
Timeout: 10000ms
Error: element(s) not found

Call log:
  - Expect "toBeVisible" locator('[name="editor-canvas"]').contentFrame().getByRole('document', { name: 'Block: Page List' }) with timeout 10000ms
  - waiting for locator('[name="editor-canvas"]').contentFrame().getByRole('document', { name: 'Block: Page List' })

    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/blocks/navigation.spec.js:34:34

refuses the drop and uploads nothing in /test/e2e/specs/editor/various/single-file-placeholder-drop.spec.js, passed after 1 failed attempt.

Error: expect(received).toHaveLength(expected)

Expected length: 0
Received length: 1
Received array:  [{"_links": {"about": [{"href": "http://localhost:8889/wp-json/wp/v2/types/attachment"}], "author": [{"embeddable": true, "href": "http://localhost:8889/wp-json/wp/v2/users/1"}], "collection": [{"href": "http://localhost:8889/wp-json/wp/v2/media"}], "curies": [{"href": "https://api.w.org/{rel}", "name": "wp", "templated": true}], "replies": [{"embeddable": true, "href": "http://localhost:8889/wp-json/wp/v2/comments?post=244"}], "self": [{"href": "http://localhost:8889/wp-json/wp/v2/media/244", "targetHints": {"allow": ["GET", "POST", "PUT", "PATCH", "DELETE"]}}], "wp:attached-to": [{"embeddable": true, "href": "http://localhost:8889/wp-json/wp/v2/posts/243", "id": 243, "post_type": "post"}]}, "alt_text": "", "author": 1, "caption": {"rendered": ""}, "class_list": ["post-244", "attachment", "type-attachment", "status-inherit", "hentry", "entry"], "comment_status": "open", "date": "2026-10-15T15:23:52", "date_gmt": "2026-10-15T15:23:52", "description": {"rendered": "<p class=\"attachment\"><a href='http://localhost:8889/wp-content/uploads/2026/10/67966720-f621-4fac-ad55-808a93e7d61a.png'><img loading=\"lazy\" decoding=\"async\" width=\"10\" height=\"10\" src=\"http://localhost:8889/wp-content/uploads/2026/10/67966720-f621-4fac-ad55-808a93e7d61a.png\" class=\"attachment-medium size-medium\" alt=\"\" style=\"width:100%;height:100%;max-width:10px;\" /></a></p>
"}, "featured_media": 0, "filename": "67966720-f621-4fac-ad55-808a93e7d61a.png", "filesize": 80, "guid": {"rendered": "http://localhost:8889/wp-content/uploads/2026/10/67966720-f621-4fac-ad55-808a93e7d61a.png"}, "id": 244, "link": "http://localhost:8889/?attachment_id=244", "media_details": {"file": "2026/10/67966720-f621-4fac-ad55-808a93e7d61a.png", "filesize": 80, "height": 10, "image_meta": {"alt": "", "aperture": "0", "camera": "", "caption": "", "copyright": "", "created_timestamp": "0", "credit": "", "focal_length": "0", "iso": "0", "keywords": [], "orientation": "0", "shutter_speed": "0", "title": ""}, "sizes": {}, "width": 10}, "media_type": "image", "meta": [], "mime_type": "image/png", "modified": "2026-10-15T15:23:52", "modified_gmt": "2026-10-15T15:23:52", "ping_status": "closed", "post": 243, "slug": "67966720-f621-4fac-ad55-808a93e7d61a", "source_url": "http://localhost:8889/wp-content/uploads/2026/10/67966720-f621-4fac-ad55-808a93e7d61a.png", "status": "inherit", "template": "", "title": {"rendered": "67966720-f621-4fac-ad55-808a93e7d61a"}, "type": "attachment"}]
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/single-file-placeholder-drop.spec.js:71:45

_{a6040dc Run}

[Copilot]

🟢 Approval recommended

The focused filtering handles stale documents while preserving editable fields, with regression coverage and no identified blocking issues.

0 open findings

What changed in this PR

Prevents stale read-only taxonomy data from marking unchanged terms as dirty during collaboration.

Changes:

• Filters read-only fields when writing and reading shared taxonomy documents, including older documents.
• Preserves editable and plugin fields.
• Adds regression coverage and documents the fix.

File	Description
test/​e2e/​specs/​editor/​collaboration/​http-only/​collaboration-taxonomy-record-dirty.spec.ts	Reproduces category count changes between sessions.
packages/​core-data/​src/​utils/​test/​crdt.jsdom.test.ts	Tests filtering and preservation of editable fields.
packages/​core-data/​src/​utils/​crdt.ts	Introduces taxonomy-specific read/write filtering.
packages/​core-data/​src/​entities.js	Applies the taxonomy sync configuration.
packages/​core-data/​CHANGELOG.md	Records the bug fix.

🧠 Review effort: Balanced

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[ciampo]

Seeing CI errors across a bunch of PRs, I'm going to merge this PR to unblock things