Deprecation: #94979 - Using CacheManager or Database Connections during TYPO3 bootstrap

Description

TYPO3 now triggers a PHP E_USER_DEPRECATED error if extension authors or site admins have code in their ext_localconf.php, Configuration/TCA/* configuration files or ext_tables.php, that calls the \TYPO3\CMS\Core\Cache\CacheManager or interacts with the database.

This is important for extension authors as TYPO3 will become stricter in the future in terms of booting up TYPO3's Core Configuration, making typical requests much faster, as all configuration can be cached away. When using TYPO3 in a build environment, this will also lead to possibilities to pre-warmup caches during the build phase of a new deployment.

Impact

Accessing the database and utilizing the Cache Manager in these files will trigger a PHP E_USER_DEPRECATED error.

Affected Installations

TYPO3 installations with extensions using Cache Manager or Database Connections in their configuration files (see above).

Migration

Use proper places to initialize extensions, and only when needed to reduce the general time to boot up TYPO3's configuration.