Pantheon release notes

The Drupal CMS upstream has been updated to version 2. Newly created sites using the Drupal CMS upstream will now use Drupal CMS 2, which includes a curated set of modules and configuration designed to help you get started faster.

This update only applies to sites created with the Drupal CMS upstream. Sites using the Drupal 10 or Drupal 11 upstreams are not affected. Existing Drupal CMS sites are also not affected — refer to the Drupal CMS documentation for upgrade guidance.

Our documentation has instructions on how to configure a new Drupal CMS site.

Pantheon's Solr search Drupal module, search_api_pantheon, has been updated with two new releases — 8.4.0 and 8.4.1. These releases include significant architectural improvements and enhanced developer experience.

We recommend upgrading directly to 8.4.1.

What's Changed in 8.4.0

• License corrected to GPL-2.0+ to align with Drupal standards.
• Major code refactoring resulting in a 60% reduction in code length.
• Simplified service architecture for better maintainability.
• Removed unnecessary overrides for Guzzle, Endpoint, and the Solarium client.
• Improved local development experience. Server connector configuration fields are now editable in local environments and automatically overridden when deployed to Pantheon.
• Drush commands automatically use the first enabled server with the Pantheon connector. The server_id argument is no longer needed or accepted.
  • For more details, see the diagnostic commands section in README.md: https://git.drupalcode.org/project/search_api_pantheon/-/blob/8.4.x/README.md#diagnostic-commands

Dependency Updates:

• Removed direct dependencies on guzzlehttp/guzzle, symfony/finder, symfony/yaml, and other packages now provided transitively through search_api_solr (these dependencies are still available but come through search_api_solr instead).
  • Impact: No action required unless custom code directly uses these services
• Removed kint-php/kint dependency.

What's Changed in 8.4.1

• Restored the search_api_pantheon_admin submodule (removed in 8.4.0) as an obsolete module to support smooth upgrades from earlier versions.

Action Required

1. Back up your database before proceeding with the upgrade.
2. Test thoroughly in a non-production environment before deploying to your live site.

Pantheon Search Server Migration

Since version 8.3.0, the default server ID is pantheon_search. New installations use this automatically. Existing sites upgrading from earlier versions can migrate from pantheon_solr8 to pantheon_search via an update hook.

If you proceed with migration, the update hook will update the server ID from pantheon_solr8 to pantheon_search, reassign all indexes to the new server, and flag content for reindexing.

After running database updates (drush updb), reindex your content:

To opt out of migration and continue using pantheon_solr8, add this to your settings.php before running database updates:

Upgrade Instructions

For detailed installation and upgrade instructions, please refer to:

• README.md
• CHANGELOG.txt

Important: Version Support

Version 8.4.x is now the only maintained version; support for 8.3.x and 8.2.x has been discontinued.

The latest update to the Pantheon Advanced Page Cache Drupal module includes a change regarding module compatibility to ensure the best performance for your site.

Key Update

The BigPipe module is fundamentally incompatible with the architecture of Pantheon's Global CDN and the functionality provided by Pantheon Advanced Page Cache module. To improve site reliability, the module will now automatically disable BigPipe when Pantheon Advanced Page Cache is enabled.

If the BigPipe module is somehow enabled after PAPC is installed, a clear error message will now be displayed on the Drupal Status Report page (/admin/reports/status).

This warning clearly highlights the fatal incompatibility and the risk of site errors.

The following updates are now available for Content Publisher:

• New release of the Pantheon Content Publisher v1.0.3 Drupal module now availabe.
• With Approval Workflows enabled, Administrators now have the option to Approve submissions direclty from the Pending approval tab of a Collection in the Content Dashboard. Previously, opening each submission in Preview mode was required.
• The experience for Smart Components has been improved for first time users.
• Upgrade Content Publisher AI metadata suggestion to use Gemini 2.5 flash instead of Gemini 2.0.
• Bug fix for our Next.js starter kit and SDK to properly support Next.js 15.5 and the use of App Router. Improve the build process by using pinned versions of dependencies.
• Fix several event tracking issues in the back-end.

Editorial note: The date has been moved from January 19 to January 26.

Tika 1.18 and 1.21 will no longer be available starting January 26, 2026. Impacted sites must upgrade to Tika 3.2 which is available via PHP Runtime Generation 2.

The Apache Tika toolkit detects and extracts metadata and structured text content from various documents using existing parser libraries. On the Pantheon platform, our customers tend to use Tika to parse PDF content for searching with Solr.

Action Required

For most customers, we expect the upgrade to be seamless and not require any manual intervention. But if your site has a custom Tika integration, we recommend you follow our documentation for upgrading to Tika 3 as soon as possible to ensure your site continues to operate as expected.

Sites which have not upgraded to Tika 3 as of January 26, 2026, will be automatically upgraded. Setting tika_version: 1 in pantheon.yml will be ignored after that date. Symlinks from the 1.xx jar filepaths (/srv/bin/tika-app-1.xx.jar) will point to the new Tika 3 jar (/opt/pantheon/tika/tika.jar). These symlinks will be removed later in 2026.

As part of Pantheon's Long-Term Support (LTS) for Drupal 7, Drupal 7.105 is now available with a critical security patch.

In order to swiftly provide security coverage for a discovered vulnerability, both 7.104 and 7.105 have been included in a 7.105 tag for the drops-7 upstream.

• 7.104: This backports a prototype pollution fix in the BBQ JavaScript library used by several popular modules, including Views, Overlay and Module Filter. Of the usages inspected, only Overlay was found to be using BBQ in a vulnerable manner. If you cannot upgrade immediately, the issue can be mitigated by uninstalling Overlay module. If Overlay is not installed, then this update is not needed.

• 7.105: This adds support for PHP 8.4. If you do not run and/or do not plan to run your site on PHP 8.4, you do not need this update. Because of the many deprecation notices added to PHP 8.4, it is recommended that ini_set('error_reporting', E_ALL & ~E_DEPRECATED & ~E_USER_DEPRECATED) or some equivalent is added to the site's settings.php file.

Action required

Apply the latest upstream update to your Drupal 7 site to receive these updates. See related documentation for how to apply core updates.

About Drupal 7 Long-Term Support

Pantheon has partnered with Tag1 Consulting to deliver security updates and maintenance for Drupal 7 sites until at least January 5, 2027. This extended support is included at no additional cost.

For configuration guidance and detailed information, visit our related documentation.

PHP Runtime Generation 2 will not include wkhtmltopdf.

Pantheon has included wkhtmltopdf with our PHP Runtime since 2012 as a tool for generating PDFs on-demand. This is commonly used by sites that have the print and entity_print Drupal modules configured.

However, wkhtmltopdf has not been updated by its maintainers for 5 years and is considered abandoned. As a result, we are not including wkhtmltopdf with PHP Runtime Generation 2.

Sites that are using wkhtmltopdf should switch to dompdf. Dompdf is a PHP-based rendering engine that can be placed inside a site's codebase. Please refer to the External Libraries documentation for information on how to make this switch.

PHP Runtime Generation 2 will begin rolling out September 24. If you need more time to switch to dompdf, we recommend opting out for now.

Editorial note: The date has been moved from November 12 to December 9.

Sites running Drupal 9.4+ will no longer be able to access Solr 3 via Pantheon Search services starting December 9, 2025. 

After this date, affected sites will not be able to fetch Solr search results or index new content using Solr 3. Views or blocks that rely on Solr-powered Search API indexes may fail to load, return no results, or throw errors.

To find out which version of Solr your site is running, go to your site in the Pantheon Dashboard > Status. Look for the Solr value in the Software Versions block. 

This follows our recent announcement of Pantheon Search no longer being available for Drupal 8-9.3.

Action Required

Affected Drupal sites will need to upgrade to Solr 8 and search_api_pantheon 8.2+. A Solr upgrade guide is available in our documentation.

Alternatively, Pantheon Search can be disabled, and site owners may choose to implement Drupal’s built-in database search or a third-party search service provider.