Suggest mode: combined feature branch for Playground testing (draft)

[adamsilverstein]

Part of #73411

What

Draft / testing-only branch. Bundles the full Suggest mode feature into one branch so the end-to-end experience can be exercised in WordPress Playground. It is not meant to be merged - the feature lands through the nine reviewable PRs below. This branch just gives reviewers and testers one place to try the whole flow.

1. #80427 - editor intent (edit/suggest/view) and experiment gate
2. #80428 - suggestion storage, REST controller, and provider
3. #80429 - block-level capture (attribute and structural)
4. #80430 - inline marker primitive
5. #80431 - inline suggestion operations
6. #80432 - review UI (Apply/Reject sidebar + summary)
7. #80433 - inline live wiring
8. #82047 - architecture documentation
9. #82048 - end-to-end test suite

One deliberate difference from the stack

Suggest mode is enabled by default here. Everywhere else it sits behind Settings > Experiments > Collaboration > Suggestion Mode, off until you turn it on. That extra step was costing testers their first session: miss it and you get a stock editor, with nothing to tell you that is the wrong one.

So this branch carries one commit of its own on top of the stack tip. It makes the window.__experimentalSuggestionMode bridge unconditional, drops the now-inert Experiments screen entry, and removes the e2e spec that covered the experiment-off state, which cannot happen here. The notice a post shows when it carries suggestion markers and the experiment is off still lives on #80427 and up, along with its coverage.

Nothing else differs. Review the gate on #80427, not here.

Testing

https://playground.wordpress.net/gutenberg.html?pr=78994

Open a post with a few paragraphs and look for Options (⋮) > Mode. No setup, no experiment to enable. A multi-paragraph post matters - some of the input handling only shows up once there is more than one block.

Then follow the full walkthrough in the tracking issue: #73411 (comment)

It covers mode switching and shortcuts, inline text suggestions, formatting, attribute and structural suggestions, the notes sidebar, undo, persistence, and the accept/reject cycle. Keeping it in one place means it stays in step with the code.

Notes

• Review and merge happen on the nine PRs above, not here.
• The branch is the tip of the stack (suggest/e2e) plus the single default-on commit described above. That is why the diff here is the sum of all nine plus a few lines.
• Refreshed against trunk on 2026-08-25. The merge cascaded up all nine layers with no conflicts, and the feature delta came through unchanged.
• e2e coverage lives in test/e2e/specs/editor/various/suggestion-mode*.spec.ts, plus test/e2e/specs/site-editor/suggestion-mode-intent-shortcuts.spec.ts.
• Architecture write-up: docs/explanations/architecture/suggestions.md.
• Full map and rationale: Add Suggestion mode with Notes #73411.

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AI Use

Built with 🤖 Claude Code over a few rounds of back and forth, and Claude wrote this description too. I will review and test.

[github-actions]

Size Change: +33.1 kB (+0.42%)

Total Size: 7.95 MB

📦 View Changed

Filename	Size	Change
build/scripts/block-editor/index.min.js	475 kB	+125 B (+0.03%)
build/scripts/core-data/index.min.js	37.4 kB	+7 B (+0.02%)
build/scripts/editor/index.min.js	608 kB	+29.6 kB (+5.11%)	🔍
build/styles/block-editor/content-rtl.css	6.22 kB	+562 B (+9.93%)	⚠️
build/styles/block-editor/content-rtl.min.css	4.67 kB	+528 B (+12.75%)	⚠️
build/styles/block-editor/content.css	6.22 kB	+562 B (+9.93%)	⚠️
build/styles/block-editor/content.min.css	4.67 kB	+532 B (+12.87%)	⚠️
build/styles/block-editor/style-rtl.css	20.4 kB	+171 B (+0.85%)
build/styles/block-editor/style-rtl.min.css	17.3 kB	+122 B (+0.71%)
build/styles/block-editor/style.css	20.4 kB	+168 B (+0.83%)
build/styles/block-editor/style.min.css	17.3 kB	+122 B (+0.71%)
build/styles/editor/style-rtl.css	32.1 kB	+179 B (+0.56%)
build/styles/editor/style-rtl.min.css	27.4 kB	+164 B (+0.6%)
build/styles/editor/style.css	32.2 kB	+179 B (+0.56%)
build/styles/editor/style.min.css	27.4 kB	+163 B (+0.6%)

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[github-actions]

Flaky tests detected in 277c3ec.
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.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/32911895936
📝 Reported tests:

Navigates the items list via UP/DOWN arrow keys in /test/e2e/specs/site-editor/dataviews-list-layout-keyboard.spec.js, passed after 1 failed attempt.

Error: expect(locator).toBeFocused() failed

Locator:  getByLabel('Page Two')
Expected: focused
Received: inactive
Timeout:  5000ms

Call log:
  - Expect "toBeFocused" with timeout 5000ms
  - waiting for getByLabel('Page Two')
    14 × locator resolved to <button type="button" tabindex="-1" aria-pressed="false" id="view-list-0-465-item-wrapper" class="dataviews-view-list__item" aria-labelledby="view-list-0-465-label" aria-describedby="view-list-0-465-description"></button>
       - unexpected value "inactive"

    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/site-editor/dataviews-list-layout-keyboard.spec.js:112:49

[adamsilverstein]

Fix: empty inserted block no longer becomes a suggestion

Bug: In Suggest mode, clicking the default block appender (the empty space below the last block) inserted an unmodified default paragraph, and the store interceptor's new-block branch immediately tagged it pending-insert and wrote a block-insert-after op — surfacing an "Insert block: paragraph" suggestion for a block the user hadn't put anything into.

Fix: Defer the insertion suggestion while the new block is still an unmodified default block. The interceptor now skips it without recording a snapshot, so the next fire — once the block has content — re-enters the new-block branch and registers the insertion. A suggestion is only created once the user actually types into the block.

Guard added in store-interceptor.js (isUnmodifiedDefaultBlock), plus an e2e test covering the empty-appender case and the type-to-suggest follow-through. All 10 suggestion-mode.spec.js tests pass locally (red→green verified).

Committed here in c63392f, and backported to the insert-mechanism PR #77971 (where this code originates) in c268952.

[adamsilverstein]

Fixed the "Format: content" note for whitespace-only suggestions.

Cause: typing only whitespace in Suggest mode produces an inline-suggestion op whose resolved text is all spaces. summarizeOperations required that text to survive a trim() and then ran it through ellipsize() (which collapses/trims whitespace), so a pure-whitespace edit became an empty quote and fell through to the generic Format: content label.

Fix: render the marker text verbatim via a new clampText() helper that caps length without collapsing whitespace, and only fall back to the attribute label when no text resolves (marker edited away). A typed space now reads Add: " ".

Added a unit case (quotes a whitespace-only inline-suggestion add verbatim) and an e2e regression in suggestion-mode.spec.js. Backported to the review PR #79282 (try/inline-suggestions-phase2).