Command Palette: Add site switcher command

[dsas]

Fixes DOTCOM-15345

Proposed changes:

• Add a new site switcher feature to the WordPress Command Palette (requires WP 6.9+)
• Implement REST API proxy endpoint at /jetpack/v4/sites/compact to fetch user's WordPress.com sites via the user's Jetpack connection
• Add client-side localStorage caching (1 hour duration) with user-specific cache keys to minimize API requests
• Implement search filtering to quickly find sites by name or domain
• Display site icons with fallback to generic site logo
• Support dynamic command labels based on whether site has a name or just domain

Implementation details:

• _inc/site-switcher-endpoint.php: REST endpoint for Jetpack sites that proxies the public-api endpoint
• _inc/site-switcher.php: JS enqueueing, and config
• _inc/site-switcher.js: React hooks-based command loader with search filtering and caching
• Commands show as "Switch to Site Name (domain.com)" or "Switch to: domain.com" if no name
• Generic search terms like "site" or "switch site" show all sites; specific searches filter results

Other information:

• Have you written new tests for your changes, if applicable? - No tests added (following pattern of other _inc/*.js files)
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

Does this pull request change what data or activity we track or use?

Not really. This feature only fetches existing site data through the established Jetpack connection API.

Testing instructions:

Prerequisites:

• Jetpack plugin installed and connected to WordPress.com
• User must have multiple WordPress.com sites

Testing steps:

1. Install and activate Jetpack plugin from this branch
   On Simple you need to also apply 198424-ghe-Automattic/wpcom
2. Ensure your site is connected to WordPress.com with a user account that has multiple sites
3. On a Jetpack site navigate to any wp-admin page, on a simple or WoA site then navigate to the site-editor (core command palette is blocked by wp command palette otherwise)
4. Open the Command Palette:
   • Mac: Cmd + K
   • Windows/Linux: Ctrl + K
5. Type "site" or "switch site" - you should see all your WordPress.com sites listed
6. Try searching for a specific site name or domain - results should filter accordingly
7. Click on a site command - you should be redirected to that site's wp-admin

Expected behavior:

• All sites show on search for generic keywords
• Search filters work for both site names and domains
• Icons display correctly (site-specific or fallback logo)
• Navigation to selected site works
• Subsequent page loads use cached data (check Network tab - no compact request for 1 hour)

Cache testing:

1. Open browser DevTools > Network tab
2. Open command palette and search for sites - you should see a request to /jetpack/v4/sites/compact
3. Reload the page and open command palette again - no new request (using localStorage cache)
4. Wait 1 hour or manually clear localStorage to see cache refresh

Screen.Recording.2025-12-18.at.11.48.56.mov

[github-actions]

Thank you for your PR!

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Follow this PR Review Process:

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Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen as soon as you deploy your changes after merging this PR (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly:
  • Scheduled release: January 6, 2026

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the dotcom-15345-command-palette-integrate-the-new-site-switch-commands-into branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack dotcom-15345-command-palette-integrate-the-new-site-switch-commands-into

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/load-jetpack.php	1/42 (2.38%)	-0.06%	1 ❤️‍🩹

2 files are newly checked for coverage.

File	Coverage
projects/plugins/jetpack/_inc/site-switcher.php	0/40 (0.00%) 💔
projects/plugins/jetpack/_inc/site-switcher-endpoint.php	9/50 (18.00%) 💔

Full summary · PHP report · JS report

_{Coverage check overridden by I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage. .}

[Copilot]

Pull request overview

This PR adds a site switcher feature to the WordPress Command Palette (WordPress 6.9+), allowing users to quickly switch between their WordPress.com connected sites directly from wp-admin. The implementation includes a REST API proxy endpoint, client-side caching via localStorage, and search filtering capabilities.

Key Changes:

• New REST API endpoint /jetpack/v4/sites/compact that proxies requests to WordPress.com's /me/sites/compact API to fetch the user's site list
• Client-side JavaScript that integrates with WordPress Command Palette using useCommandLoader hook, with 1-hour localStorage caching
• Script enqueuing logic that loads the site switcher on all admin pages

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 11 comments.

File	Description
projects/plugins/jetpack/load-jetpack.php	Includes the new site-switcher.php file in the plugin bootstrap
projects/plugins/jetpack/changelog/switch-sites-command-palette	Changelog entry documenting the enhancement
projects/plugins/jetpack/_inc/site-switcher.php	REST endpoint registration, script enqueuing, and user ID injection for cache namespacing
projects/plugins/jetpack/_inc/site-switcher.js	React-based command loader with search filtering, localStorage caching, and site navigation

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 13 comments.

---

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[simison]

Couple clarifying Qs:

• What shows up for users who have just one site?
• What shows up for users on Jetpack sites who aren't the Jetpack connection owner or aren't connected to WP.com?
• On multi-site WP installations with Jetpack, are there similar core commands and how this works alongside them?

[dsas]

• What shows up for users who have just one site?

Good question, it was just showing the current site. I've made a change to exclude the current site

• What shows up for users on Jetpack sites who aren't the Jetpack connection owner or aren't connected to WP.com?

If you're not connected then it will try to get your sites and fail (it's an authenticated endpoint), this means it won't offer you any sites to switch to.

If you are connected, but the Jetpack site connection owner is someone else, then it'll use your connection and show you just the sites you have access to.

• On multi-site WP installations with Jetpack, are there similar core commands and how this works alongside them?

There are no similar core commands at this time, at least not that I was able to find.

[simison]

If you're not connected then it will try to get your sites and fail (it's an authenticated endpoint), this means it won't offer you any sites to switch to.

Cool; there's a helper method that returns the connection status, and that would help avoid firing API request that we know would fail.