Core: Restore original clipboard after invoking userEvent.setup()

[ghengeveld]

Closes #31626

What I did

This restores the original window.navigator.clipboard instance to restore clipboard functionality after calling userEvent.setup(), which replaced it with a stub.

Users who want to test clipboard functionality should call userEvent.setup() themselves.

I've opened an issue on user-event to address this problem at the source.

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Manual testing

This section is mandatory for all contributions. If you believe no manual test is necessary, please state so explicitly. Thanks!

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli-storybook/src/sandbox-templates.ts

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook canary-release-pr.yml --field pr=<PR_NUMBER>

Greptile Summary

Fixes clipboard functionality by restoring the original window.navigator.clipboard after userEvent.setup() is invoked in test environment.

• Captures and preserves original clipboard object before userEvent.setup() modifies it
• Uses Object.defineProperty to restore original clipboard functionality after tests
• Prevents clipboard functionality from being broken by userEvent's stub implementation
• Maintains existing focus method patching behavior
• Delegates clipboard testing responsibility to users who specifically need it by having them call userEvent.setup() themselves

[greptile-apps]

LGTM

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[nx-cloud]

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---

☁️ Nx Cloud last updated this comment at 2025-06-11 20:34:58 UTC

[storybook-pr-benchmarking]

Package Benchmarks

^{Commit: 7bcaf86, ran on 11 June 2025 at 20:40:35 UTC}

The following packages have significant changes to their size or dependencies:

@storybook/addon-vitest

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storybook

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@storybook/ember

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@storybook/nextjs

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@storybook/nextjs-vite

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@storybook/react-native-web-vite

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@storybook/react-vite

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@storybook/react-webpack5

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sb

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@storybook/cli

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Dependency count	216	324	🚨 +108 🚨
Self size	582 KB	244 KB	🎉 -338 KB 🎉
Dependency size	94.67 MB	98.82 MB	🚨 +4.15 MB 🚨
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@storybook/codemod

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Dependency count	185	267	🚨 +82 🚨
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create-storybook

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@storybook/preset-react-webpack

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Dependency size	30.51 MB	30.50 MB	🎉 -15 KB 🎉
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