[ntsekouras]

What

Follow up of: #85167

After the migration to the @wordpress/ui SelectControl (#84345, #84546), selects with a default option stored as an empty string show the Select placeholder instead of the option's label when it's selected. Base UI treats an empty string value as no selection.

This PR fixes the rest of the affected selects:

1. Block position: Default.
2. Text shadow (when there are enough presets to render the select): Default.
3. Template part HTML element: Default based on area (<header>).
4. PostTemplatePanel / PageTemplate on classic themes: the default template. Core doesn't render these since Editor: Stabilize the DataForm-based inspector #85081, so this only affects plugins that render them.
5. Legacy widget: Select widget.

The options that are a choice of their own (1-4) get a non-empty value that is mapped back to '', so the saved values don't change. Select widget means no widget, so it uses null instead, which Base UI renders with its label.

It also adds a development warning to SelectControl when an item has an empty string value, so it doesn't regress again.

Testing Instructions

1. With a block theme, in the post editor add a Group block. In the block settings open the Position options menu, enable Position and observe the select shows Default. Switch to Sticky and back to Default.
2. In the site editor open a template with a header, select the Header template part and in the block Settings tab open the Advanced panel. Observe the HTML element select shows Default based on area (<header>).
3. In Global Styles > Typography, open the text shadow control with enough presets and observe the select shows Default.
4. With a classic theme, go to Appearance > Widgets, add a Legacy Widget block and observe the select shows Select widget.
5. Everything should work as before.

Screenshots or screencast

Use of AI Tools

Generated with Opus 5.5 and adjusted/reviewed manually.

[github-actions]

🤖 PR meta 🤖

🎉 Props

If you're merging code through a pull request on GitHub, copy and paste the following into the bottom of the merge commit message.

Co-authored-by: ntsekouras <ntsekouras@git.wordpress.org>
Co-authored-by: ciampo <mciampini@git.wordpress.org>
Co-authored-by: mirka <0mirka00@git.wordpress.org>
Co-authored-by: oandregal <oandregal@git.wordpress.org>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

Updated as activity occurs, without notifying anyone named here. Add the props-bot label to refresh.

📦 Bundle size

Size Change: +141 B (0%)

Total Size: 8.97 MB

📦 View Changed

Filename	Size	Change
build/scripts/block-editor/index.min.js	604 kB	+70 B (+0.01%)
build/scripts/block-library/index.min.js	442 kB	+24 B (+0.01%)
build/scripts/editor/index.min.js	614 kB	+42 B (+0.01%)
build/scripts/widgets/index.min.js	70.3 kB	+5 B (+0.01%)

_{77d495c Run}

⚡ Performance

Show the results

Client side metrics exclude the server response time.

front-end-block-theme

Metric	c40fb42	trunk	% Change
timeToFirstByte	37.5 ms +2.93% -6.8%	37.6 ms +8.24% -7.71%	-0.27%
largestContentfulPaint	66 ms +9.09% -6.06%	64 ms +9.38% -3.13%	3.13%
lcpMinusTtfb	27.6 ms +20.65% -6.16%	26.7 ms +13.67% -3.93%	3.37%
wpBeforeTemplate	19.38 ms +6.66% -5.73%	19.36 ms +16.37% -6.56%	0.1%
wpTemplate	14.04 ms +10.47% -3.92%	13.7 ms +10.36% -2.85%	2.48%
wpTotal	34.23 ms +3.1% -7.16%	34.33 ms +8.48% -7.78%	-0.29%
wpMemoryUsage	7.64 MB +0% -0%	7.61 MB +0% -0%	0.46%
wpDbQueries	16 +0% -0%	16 +0% -0%	0%

front-end-classic-theme

Metric	c40fb42	trunk	% Change
timeToFirstByte	29.7 ms +21.04% -4.38%	28.5 ms +9.3% -6.14%	4.21%
largestContentfulPaint	66 ms +18.18% -3.03%	64 ms +3.13% -6.25%	3.13%
lcpMinusTtfb	36.05 ms +19.56% -3.33%	34.5 ms +2.9% -1.74%	4.49%
wpBeforeTemplate	17.87 ms +13.71% -2.85%	17.41 ms +10.68% -7.52%	2.64%
wpTemplate	8.89 ms +25.65% -7.99%	8.43 ms +7.35% -10.44%	5.46%
wpTotal	27.05 ms +20.74% -5.36%	25.83 ms +9.72% -6.81%	4.72%
wpMemoryUsage	6.22 MB +0% -0%	6.19 MB +0% -0%	0.58%
wpDbQueries	9 +0% -0%	9 +0% -0%	0%

media-processing

Metric	c40fb42	trunk	% Change
mediaProcessingJpeg	230.09 ms +9.14% -1.78%	230.5 ms +0.82% -0.41%	-0.18%
mediaProcessingAvif	3747.37 ms +1.3% -1.04%	3747.28 ms +1.29% -0.38%	0%
mediaProcessingJpegToAvif	2587.86 ms +1.11% -0.58%	2617.47 ms +0.83% -0.84%	-1.13%

media-upload

Metric	c40fb42	trunk	% Change
jpegUploadProcessing	1423.04 ms +1.01% -0.75%	1407.45 ms +0.4% -0.68%	1.11%
pngUploadProcessing	194.74 ms +6.68% -2.81%	190.98 ms +4.29% -9.01%	1.97%
largeJpegUploadProcessing	1411.42 ms +0.56% -0.75%	1411.83 ms +0.5% -0.46%	-0.03%
multipleImageUploadProcessing	1507.9 ms +0.77% -1.22%	1469.35 ms +0.29% -0.11%	2.62%

post-editor

Metric	c40fb42	trunk	% Change
serverResponse	501.31 ms +4.43% -3.9%	535.05 ms +0.61% -6.63%	-6.31%
firstPaint	445.24 ms +17.24% -32.74%	356.34 ms +40.16% -12.64%	24.95%
domContentLoaded	1240.24 ms +1.67% -4.32%	1237.19 ms +1.88% -2.29%	0.25%
loaded	1241.41 ms +1.66% -4.32%	1238.54 ms +1.87% -2.3%	0.23%
firstContentfulPaint	519.65 ms +11.72% -4.07%	522.31 ms +3.43% -4.38%	-0.51%
firstBlock	3822.54 ms +3.36% -1.87%	3942.33 ms +0.18% -5.33%	-3.04%
type	19.79 ms +1.87% -2.43%	17.72 ms +5.76% -4.57%	11.68%
typeWithoutInspector	18.84 ms +3.13% -4.14%	18.56 ms +0.86% -5.06%	1.51%
typeWithTopToolbar	25.29 ms +7% -2.65%	23.1 ms +10.61% -2.81%	9.48%
typeContainer	9.46 ms +8.88% -7.72%	9.37 ms +11.95% -2.77%	0.96%
focus	127.44 ms +11.32% -1.99%	128.96 ms +4.27% -5.83%	-1.18%
firstFocus	250.32 ms +0% -0%	248.18 ms +0% -0%	0.86%
selectAll	618.94 ms +0.01% -2%	616.22 ms +1.36% -1.11%	0.44%
listViewOpen	85.89 ms +14.16% -11.71%	86.7 ms +2.26% -4.64%	-0.93%
inserterOpen	44.84 ms +13.78% -3.95%	43.77 ms +8.04% -8.52%	2.44%
inserterHover	12.85 ms +13.85% -6.46%	11.63 ms +8.51% -6.53%	10.49%
inserterSearch	8.19 ms +9.52% -8.18%	8.4 ms +5.6% -8.33%	-2.5%
loadPatterns	668.46 ms +2.4% -6.83%	670.68 ms +2.56% -1.5%	-0.33%
wpTotal	490.03 ms +4.74% -3.79%	523.73 ms +0.74% -6.62%	-6.43%
wpMemoryUsage	14.66 MB +0% -0%	14.63 MB +0% -0%	0.26%
wpDbQueries	54.5 +0.92% -0.92%	55 +0% -1.82%	-0.91%

site-editor

Metric	c40fb42	trunk	% Change
serverResponse	425.97 ms +2.43% -8.54%	401.94 ms +4.87% -6.89%	5.98%
firstPaint	261.86 ms +35.82% -7.49%	249.66 ms +7.05% -5.89%	4.89%
domContentLoaded	1274.71 ms +4.95% -1.67%	1252.61 ms +1.29% -1.65%	1.76%
loaded	1276.12 ms +4.92% -1.67%	1253.67 ms +1.29% -1.63%	1.79%
firstContentfulPaint	533.08 ms +4.34% -4.36%	509.89 ms +3.09% -12.07%	4.55%
firstBlock	4830.82 ms +0.8% -0.51%	4750.09 ms +1.55% -0.61%	1.7%
type	21.44 ms +7.56% -4.94%	21.97 ms +3.1% -2.59%	-2.41%
navigate	126.74 ms +8.98% -1.19%	123.94 ms +15.31% -1.5%	2.26%
loadPatterns	1333.48 ms +3.54% -4.14%	1392.52 ms +4.99% -14.14%	-4.24%
loadPages	1065.6 ms +7.35% -3.9%	1088.99 ms +7.13% -6.2%	-2.15%
wpTotal	415.81 ms +2.38% -8.94%	391.84 ms +5% -7.21%	6.12%
wpMemoryUsage	12.70 MB +0% -0%	12.66 MB +0% -0%	0.29%
wpDbQueries	44 +2.27% -0%	44 +2.27% -0%	0%

_{77d495c 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.

Regression: updating a specific option will only change its value and will not corrupt others in /test/e2e/specs/editor/various/core-settings.spec.js, passed after 1 failed attempt.

Error: expect(received).toStrictEqual(expected) // deep equality

- Expected  - 1
+ Received  + 1

  Array [
    "rewrite_rules",
-   "SERIALIZED DATA",
+   "",
  ]
    at forEach (/home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/core-settings.spec.js:46:26)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/core-settings.spec.js:43:35

keeps the blocks selected after dropping a multi-selection in /test/e2e/specs/editor/various/draggable-blocks.spec.js, passed after 1 failed attempt.

TypeError: Cannot read properties of null (reading 'y')
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:824:57
    at dragSelectionBelowLanding (/home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:823:3)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:908:3

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=223"}], "self": [{"href": "http://localhost:8889/wp-json/wp/v2/media/223", "targetHints": {"allow": ["GET", "POST", "PUT", "PATCH", "DELETE"]}}], "wp:attached-to": [{"embeddable": true, "href": "http://localhost:8889/wp-json/wp/v2/posts/222", "id": 222, "post_type": "post"}]}, "alt_text": "", "author": 1, "caption": {"rendered": ""}, "class_list": ["post-223", "attachment", "type-attachment", "status-inherit", "hentry", "entry"], "comment_status": "open", "date": "2026-10-20T12:50:53", "date_gmt": "2026-10-20T12:50:53", "description": {"rendered": "<p class=\"attachment\"><a href='http://localhost:8889/wp-content/uploads/2026/10/4435665a-f7c3-4fb1-92ba-e101dc4d1915.png'><img loading=\"lazy\" decoding=\"async\" width=\"10\" height=\"10\" src=\"http://localhost:8889/wp-content/uploads/2026/10/4435665a-f7c3-4fb1-92ba-e101dc4d1915.png\" class=\"attachment-medium size-medium\" alt=\"\" style=\"width:100%;height:100%;max-width:10px;\" /></a></p>
"}, "featured_media": 0, "filename": "4435665a-f7c3-4fb1-92ba-e101dc4d1915.png", "filesize": 80, "guid": {"rendered": "http://localhost:8889/wp-content/uploads/2026/10/4435665a-f7c3-4fb1-92ba-e101dc4d1915.png"}, "id": 223, "link": "http://localhost:8889/?attachment_id=223", "media_details": {"file": "2026/10/4435665a-f7c3-4fb1-92ba-e101dc4d1915.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": "2026-10-20T12:50:53", "modified_gmt": "2026-10-20T12:50:53", "ping_status": "closed", "post": 222, "slug": "4435665a-f7c3-4fb1-92ba-e101dc4d1915", "source_url": "http://localhost:8889/wp-content/uploads/2026/10/4435665a-f7c3-4fb1-92ba-e101dc4d1915.png", "status": "inherit", "template": "", "title": {"rendered": "4435665a-f7c3-4fb1-92ba-e101dc4d1915"}, "type": "attachment"}]
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/single-file-placeholder-drop.spec.js:71:45

restores the blocks when a multi-selection drag is canceled in /test/e2e/specs/editor/various/draggable-blocks.spec.js, passed after 1 failed attempt.

TypeError: Cannot read properties of null (reading 'y')
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:824:57
    at dragSelectionBelowLanding (/home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:823:3)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/draggable-blocks.spec.js:871:3

_{77d495c Run}

[oandregal]

This sounds like a big enough issue that warrants to be fixed upstream (the wordpress/ui package)? cc @ciampo @mirka

[ciampo]

This sounds like a big enough issue that warrants to be fixed upstream (the wordpress/ui package)? cc @ciampo @mirka

This is not an "issue" or a bug per se, it's just how the component is meant to function, although I understand that it can trip consumers.

I think that the development warning, documentation, and tests in @wordpress/ui are already a good set of changes. At most, we could consider adding a dedicated migration guide that highlights this particular aspect.

The default-to-empty-string conversions should stay in the consumers, preserving their saved values and the shared component's native form serialization.

[mirka]

I'll also work on a migration guide with these findings from all the migrations.

[ciampo]

LGTM 🚀

[github-actions]

I just cherry-picked this PR to the wp/7.2 branch to get it included in the next release: 9ac2f99