Forms: fix outlined leading radius

[CGastrell]

Fixes FORMS-424

Proposed changes:

This PR adds initial border style settings for the leading notch used on Outlined styles.

Before:

After:

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)?

Jetpack product discussion

p1763644719158009-slack-C086RGTJT1D

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

No

Testing instructions:

Use a theme showing the symptoms, like Assembler. Insert a form, see that inputs have their border radius as set by theme.
Switch the form style to Outlined. See that border radius on the inputs, until changed, remain the same as before switching the style.
Confirm the frontend reflects the style.
Try one or two more themes to confirm no regressions.

[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 fix/forms-outlined-leading-radius branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack fix/forms-outlined-leading-radius

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!

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• ✅ Add changelog entries to affected projects
  

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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).
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  • Scheduled release: December 2, 2025

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[jp-launch-control]

Code Coverage Summary

This PR did not change code coverage!

That could be good or bad, depending on the situation. Everything covered before, and still is? Great! Nothing was covered before? Not so great. 🤷

Full summary · PHP report · JS report

_{Coverage check overridden by Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR .}

[Copilot]

Pull request overview

This PR fixes a visual inconsistency in the outlined form style where the leading notch element was missing border style and border radius properties in the editor view. The fix ensures the editor appearance matches the frontend rendering and maintains consistency with the other notch elements (notch, filler, and trailing).

• Adds border-style and border-radius CSS properties to .notched-label__leading in editor styles
• Aligns editor styles with existing frontend styles in grunion.scss
• Ensures consistent border rendering across all notch elements in outlined form styles

Reviewed changes

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

File	Description
projects/packages/forms/src/blocks/contact-form/editor.scss	Adds missing border-style and border-radius properties to the leading notch element to match frontend styles and other notch elements
projects/packages/forms/changelog/fix-forms-outlined-leading-radius	Documents the patch fix for the outlined style leading notch border settings

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[edanzer]

Looks good! LGTM.