Social Previews: Remove maxLines limit from Nextdoor preview

[gmjuhasz]

Related to Automattic/jetpack#45938

Proposed Changes

• Remove maxLines: FEED_TEXT_MAX_LINES from Nextdoor preview component to allow full text display

Why are these changes being made?

The Nextdoor preview had a maxLines: 2 limit that was cutting off content when the excerpt contained Gutenberg block comments (e.g., <!-- wp:paragraph -->). These HTML comments were being counted as lines, causing the preview to only show the title and truncate the actual description.

Facebook's preview doesn't have this line limit and properly displays title + description despite having the same Gutenberg block comments in the excerpt. By removing the line limit from Nextdoor, it now behaves consistently with Facebook.

The maxChars: 160 limit is still in place for character truncation, which is the appropriate constraint.

Testing Instructions

For Jetpack Testing:

To test this change in Jetpack before it's published to npm, you need to link the local package:

1. In wp-calypso/packages/social-previews/, run pnpm link --global
2. In jetpack/projects/js-packages/publicize-components/, run pnpm link --global @automattic/social-previews
3. In wp-calypso/packages/social-previews/, rebuild with yarn build (or use fswatch for auto-rebuild)
4. In jetpack/, rebuild with jetpack build packages/publicize
5. Don't forget to run pnpm unlink in Jetpack when done

Testing Steps:

Test with Automattic/jetpack#45938

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you tested accessibility for your changes?
• Have you used memoizing on expensive computations?
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-162111

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-162111&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-162111&env=a8c-for-agencies

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• help-center
• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug fix/social/remove-nextdoor-preview-limit on your sandbox.