Remove support for sx from Details component

[llastflowers]

Closes https://github.com/github/primer/issues/5784

Current sx usage: 2

✅ sx usages are only in repos other than github-ui; those usages have been added to the tracking issue

Changelog

Removed

Remove support for sx from the AvatarStack component, and associated stories, docs, and tests

Rollout strategy

• Major release; if selected, include a written rollout or migration plan

We are using the @primer/styled-react component to mitigate removing sx usage. We will make sure usage is updated upstream before merging.

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github (Learn more about how to run integration tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: b1474a2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@primer/react	Major
@primer/styled-react	Major

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

👋 Hi, this pull request contains changes to the source code that github/github depends on. If you are GitHub staff, we recommend testing these changes with github/github using the integration workflow. Thanks!

[github-actions]

size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	87.97 KB (+0.04% 🔺)
packages/react/dist/browser.umd.js	88.08 KB (-0.1% 🔽)

[Copilot]

Pull Request Overview

This PR removes support for the sx prop from the Details component as part of a broader effort to migrate away from the styled-system approach. The change replaces the BoxWithFallback wrapper with a native HTML details element and removes all sx-related type definitions and documentation.

• Removes sx prop support from the Details component and its type definitions
• Replaces BoxWithFallback wrapper with native HTML details element
• Updates documentation and removes deprecated sx props from docs.json

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

File	Description
packages/react/src/Details/Details.tsx	Removes sx imports, replaces BoxWithFallback with native details element, updates type definitions
packages/react/src/Details/Details.docs.json	Removes deprecated sx prop documentation from component and subcomponent props
e2e/components/Details.test.ts	Removes SX Prop Stress Test story from visual regression tests
.changeset/strange-knives-study.md	Adds changeset entry for major version bump due to breaking change

[francinelucca]

Note: make sure to run integration checks 🙏

[primer-integration]

👋 Hi from github/github-ui! Your integration PR is ready: https://github.com/github/github-ui/pull/1935

[primer-integration]

🟢 ci completed with status success.