jetpack-mu-wpcom: Enable the enhanced code block by default

[sirreal]

Proposed changes:

Enable the enhanced Code block by default.

See https://wordpress.com/blog/2026/01/19/introducing-the-enhanced-code-block/

Other information:

• Have you written new tests for your changes, if applicable?
• 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)?

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

No

Testing instructions:

• Test this PR on a WoA site.
• The enhanced Code block should be enabled.

[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 (WordPress.com Site Helper), and enable the code-block/enable-by-default branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack-mu-wpcom-plugin code-block/enable-by-default

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

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Review, ...).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

---

Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
3. You can use GitHub's Reviewers functionality to request a review.
4. When it's reviewed and merged, you will be pinged in Slack to deploy the changes to WordPress.com simple once the build is done.

If you have questions about anything, reach out in #jetpack-developers for guidance!

[Copilot]

Pull request overview

This PR enables the enhanced Code block by default in the jetpack-mu-wpcom package by changing the default filter value from false to true.

Changes:

• Changed the default value of the jetpack_mu_wpcom_should_load_code_block filter from false to true to enable the enhanced Code block by default

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
projects/packages/jetpack-mu-wpcom/src/features/wpcom-blocks/code/class-code-block.php	Changed the default filter value to enable the enhanced Code block
projects/packages/jetpack-mu-wpcom/changelog/enable-code-block	Added changelog entry describing the change

[jp-launch-control]

Code Coverage Summary

Cannot generate coverage summary while tests are failing. 🤐

Please fix the tests, or re-run the Code coverage job if it was something being flaky.

Full summary · PHP report

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

[sirreal]

@copilot Solve the test problems in this branch. wpcomsh php tests run and jetpack-mu-wpcom has not been compiled so it's missing some asset files that are generated by the javascript compilation.

[Copilot]

@sirreal I've opened a new pull request, #46681, to work on those changes. Once the pull request is ready, I'll request review from you.