Themes: Fix stuck spinner and broken retry after canceling a theme update from the details overlay

[irozum]

Canceling the filesystem-credentials modal after clicking "update now" inside the theme details overlay (Appearance → Themes → click a theme's screenshot → "update now") left the overlay's "Updating…" spinner stuck forever and broke the retry click, even though the same action from the theme grid card's own update link reset correctly. This was caused by two compounding bugs in wp.updates: the overlay's notice had no data-slug, so the cancel handler's selector never reached it at all; and even once reachable, updateTheme() stored each notice's original text via $notice.data('originaltext', $notice.html()) on a combined multi-element jQuery collection, where both .data() and .html() only operate on the first element — so the overlay and the grid card ended up sharing one snapshot, and canceling could paste one notice's markup into the other instead of restoring each one's own content.

This adds a data-slug attribute to the theme details overlay root in Details.render() (mirroring the existing convention already used by the grid card view) and marks the overlay's update notice with the same update-message class the grid card uses, so both notices are reachable through one selector. updateTheme() and the credential-modal-cancel handler in updates.js now iterate matched notices with .each() so each one's original text is read and restored independently instead of relying on jQuery's first-element-only .data()/.html() behavior across a multi-element collection.

Verified with a browser harness driving the real compiled wp.updates script through the exact scenario (open overlay → update → credentials required → cancel), confirming it reproduces the reported symptom on unfixed code and is resolved after the fix, plus manual verification in a running wp-env with a forced FS_METHOD and a faked theme update.

Trac ticket: https://core.trac.wordpress.org/ticket/37669

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Sonnet 5
Used for: Root cause analysis, implementation, test coverage, and manual verification. Reviewed and directed by me throughout.

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[Copilot]

Pull request overview

Fixes a UI regression in the Themes screen where canceling the filesystem credentials modal during a theme update from the details overlay leaves the overlay “Updating…” state stuck and breaks retry behavior, by ensuring both the overlay and grid-card notices are discoverable and independently restored.

Changes:

• Add data-slug to the theme details overlay root so update/cancel handlers can target overlay notices consistently with grid cards.
• Standardize the overlay update notice by adding the update-message class and update the JS selectors accordingly.
• Update wp.updates.updateTheme() and the credential-modal-cancel handler to iterate over all matched notices and store/restore each notice’s original content independently; add a QUnit regression test covering overlay + grid notice restoration.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
tests/qunit/wp-admin/js/updates.js	Adds a regression test ensuring cancel restores both overlay and grid notices without cross-contamination.
src/wp-admin/themes.php	Marks the overlay update notice with update-message so it’s reachable by the same selectors as grid notices.
src/js/_enqueues/wp/updates.js	Fixes multi-notice handling by iterating notices when snapshotting/restoring original content; updates selectors to target both overlay and grid via data-slug.
src/js/_enqueues/wp/theme.js	Adds data-slug to the overlay root during render so JS can correctly scope notice selection in the overlay.

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[github-actions]

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