MC4WP: Mailchimp for WordPress

4.13.1
Release date: Jun 22, 2026

Forms: Improve handling of pasted <form> wrapper tags in form content.

Forms: Remove mc4wp_default_form_id option. We now default to first available form.

Forms: Improve the {email} dynamic content tag by detecting common lowercase email field names.

Misc: Adhere to DB, Security, I18n sniffs from WordPress Coding Standards.

Misc: Prevent direct access to plugin configuration files.

Misc: Remove the plugin review request from the footer of plugin admin pages.

Security: Add Patchstack vulnerability disclosure instructions to the plugin FAQ and security policy.

4.13.0
Release date: Jun 1, 2026

Improve performance by preloading core plugin classes and skipping dynamic content tag parsing when no tags are present.

Improve security for admin AJAX requests by adding a nonce check and stricter audience ID handling.

Improve dynamic content tag replacement by removing broken regular expressions.

Improve form preview output by disabling PHP error display during preview rendering.

Update JavaScript dependencies and pass admin script data using wp_add_inline_script().

4.12.6
Release date: May 26, 2026

Fix integrations losing runtime options like double opt-in when sign-up attempts are processed asynchronously. Thanks Jon Parker!

Fix Site Tracking Pixel setting not being saved when disabling it.

Improve accessibility of generated form fields by wrapping inputs in labels and using fieldsets for checkbox and radio fields.

Improve validation