Remove support for sx from CounterLabel component

[llastflowers]

Closes https://github.com/github/primer/issues/5783

Current sx usage: 5

❌ Still need to separately update github-ui components to use @primer/styled-react
github/github-ui PR: https://github.com/github/github-ui/pull/1870

Changelog

Removed

Remove support for sx from the CounterLabel 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: 984fbd5

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	89.55 KB (+0.04% 🔺)
packages/react/dist/browser.umd.js	89.61 KB (-0.01% 🔽)

[Copilot]

Pull Request Overview

This PR removes the deprecated sx prop support from the CounterLabel component as part of the migration away from styled-components to a more modern CSS-in-JS approach. The changes align with the broader effort to eliminate sx prop usage across Primer React components.

• Removes sx prop from CounterLabel component interface and implementation
• Replaces BoxWithFallback wrapper with native span element
• Updates component documentation to reflect API changes

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
packages/react/src/CounterLabel/CounterLabel.tsx	Removes SxProp type, BoxWithFallback wrapper, and simplifies to native span element
packages/react/src/CounterLabel/CounterLabel.docs.json	Removes deprecated sx prop from component documentation
.changeset/sharp-papayas-destroy.md	Adds changeset entry documenting the breaking change for major release

[siddharthkp]

Looks good!

Approving, merge whenever the supporting PR is ready!

[primer-integration]

👋 Hi from github/github-ui! Your integration PR is ready: https://github.com/github/github-ui/pull/2766

[primer-integration]

🟢 ci completed with status success.

[github-actions]

👋 Hi, there are new commits since the last successful integration test. We recommend running the integration workflow once more, unless you are sure the new changes do not affect github/github. Thanks!

[github-actions]

👋 Hi, there are new commits since the last successful integration test. We recommend running the integration workflow once more, unless you are sure the new changes do not affect github/github. Thanks!