Release: Prerelease 10.4.0-alpha.5

[github-actions]

This is an automated pull request that bumps the version from 10.4.0-alpha.4 to 10.4.0-alpha.5.
Once this pull request is merged, it will trigger a new release of version 10.4.0-alpha.5.
If you're not a core maintainer with permissions to release you can ignore this pull request.

To do

Before merging the PR, there are a few QA steps to go through:

• Add the "freeze" label to this PR, to ensure it doesn't get automatically forced pushed by new changes.
• Add the "ci:daily" label to this PR, to trigger the full test suite to run on this PR.

And for each change below:

1. Ensure the change is appropriate for the version bump. E.g. patch release should only contain patches, not new or de-stabilizing features. If a change is not appropriate, revert the PR.
2. Ensure the PR is labeled correctly with one of: "BREAKING CHANGE", "feature request", "bug", "maintenance", "dependencies", "documentation", "build", "unknown".
3. Ensure the PR title is correct, and follows the format "[Area]: [Summary]", e.g. "React: Fix hooks in CSF3 render functions". If it is not correct, change the title in the PR.
   • Areas include: React, Vue, Core, Docs, Controls, etc.
   • First word of summary indicates the type: “Add”, “Fix”, “Upgrade”, etc.
   • The entire title should fit on a line

This is a list of all the PRs merged and commits pushed directly to next, that will be part of this release:

• 🔧 Maintenance: Refactor: Extract shared PseudoStateGrid component in pseudo-states stories #34334
• 🐛 Bug: CLI: Fix Next.js Vite automigration corrupting configs already using storybook/nextjs-vite #34249
• 🐛 Bug: React-Vite: Upgrade joshwooding/vite-plugin-react-docgen-typescript to 0.7.0 #34335 (will also be patched)
• 🐛 Bug: Manager: URL-based tag filter state + filter-aware initial story selection #34283
• 🔧 Maintenance: Addon-a11y: Clear status transition timer on unmount to prevent test flake #34203 (will also be patched)
• 🐛 Bug: Builder-Vite: Use djb2 hash to prevent variable name collisions in builder-vite #34274 (will also be patched)
• ✨ Feature Request: Core: Add changeDetection feature flag #34314
• 🏗️ Build: Build: Don't check format of version JSON files #34321

If you've made any changes doing the above QA (change PR titles, revert PRs), manually trigger a re-generation of this PR with this workflow and wait for it to finish. It will wipe your progress in this to do, which is expected.

Feel free to manually commit any changes necessary to this branch after you've done the last re-generation, following the Make Manual Changes section in the docs, especially if you're making changes to the changelog.

When everything above is done:

• Merge this PR
• Follow the run of the publish action

---

Generated changelog

10.4.0-alpha.5

• Addon-a11y: Clear status transition timer on unmount to prevent test flake - #34203, thanks mixelburg!
• Builder-Vite: Use djb2 hash to prevent variable name collisions in builder-vite - #34274, thanks chida09!
• CLI: Fix Next.js Vite automigration corrupting configs already using storybook/nextjs-vite - #34249, thanks nathanjessen!
• Core: Add changeDetection feature flag - #34314, thanks valentinpalkovic!
• Manager: URL-based tag filter state + filter-aware initial story selection - #34283, thanks valentinpalkovic!
• React-Vite: Upgrade joshwooding/vite-plugin-react-docgen-typescript to 0.7.0 - #34335, thanks beeswhacks!
• Refactor: Extract shared PseudoStateGrid component in pseudo-states stories - #34334, thanks copilot-swe-agent!

[storybook-app-bot]

Package Benchmarks

^{Commit: 6de8c90, ran on 26 March 2026 at 20:17:24 UTC}

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

@storybook/nextjs-vite

	Before	After	Difference
Dependency count	92	92	0
Self size	1.12 MB	1.12 MB	0 B
Dependency size	22.73 MB	22.76 MB	🚨 +33 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react-native-web-vite

	Before	After	Difference
Dependency count	121	121	0
Self size	30 KB	30 KB	0 B
Dependency size	23.80 MB	23.83 MB	🚨 +33 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react-vite

	Before	After	Difference
Dependency count	82	82	0
Self size	35 KB	35 KB	0 B
Dependency size	20.51 MB	20.54 MB	🚨 +33 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/cli

	Before	After	Difference
Dependency count	184	184	0
Self size	780 KB	780 KB	🎉 -57 B 🎉
Dependency size	67.68 MB	67.69 MB	🚨 +12 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/codemod

	Before	After	Difference
Dependency count	177	177	0
Self size	32 KB	32 KB	🚨 +36 B 🚨
Dependency size	66.21 MB	66.22 MB	🚨 +12 KB 🚨
Bundle Size Analyzer	Link	Link