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typo3/cms-core breaking changes

Every breaking API change we have recorded in typo3/cms-core on Packagist: 2,932 breaking changes in 3 versions. Below are its newest 3 versions, removals and renames first, each with its source.

Newest change November 25, 2025

On this page

v14.0.0

716 breaking changes, first published November 25, 2025.

  • Removed TYPO3\CMS\Core\Authentication\BackendUserAuthentication::returnWebmounts
    Use getWebmounts instead. packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::$cache
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::$cache was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::$context
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::$context was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::calculateExpiryTime
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::calculateExpiryTime was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::DATETIME_EXPIRYTIME_UNLIMITED
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::DATETIME_EXPIRYTIME_UNLIMITED was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::flushByTags
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::flushByTags was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::setDefaultLifetime
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::setDefaultLifetime was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\AbstractBackend::UNLIMITED_LIFETIME
    TYPO3\CMS\Core\Cache\Backend\AbstractBackend::UNLIMITED_LIFETIME was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\FileBackend::freeze
    TYPO3\CMS\Core\Cache\Backend\FileBackend::freeze was removed in typo3/cms-core v14.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Cache\Backend\FileBackend::isFrozen
    TYPO3\CMS\Core\Cache\Backend\FileBackend::isFrozen was removed in typo3/cms-core v14.0.0 packagist.org

And 706 more in this version.

v13.0.0

1,176 breaking changes, first published January 30, 2024.

  • Removed TYPO3\CMS\Core\Attribute\AsAllowedCallable
    TYPO3\CMS\Core\Attribute\AsAllowedCallable was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__call
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__call was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__get
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__get was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__isset
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__isset was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__set
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__set was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__unset
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__unset was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::getUserId
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::getUserId was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::getUserName
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::getUserName was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::handleLoginFailure
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::handleLoginFailure was removed in typo3/cms-core v13.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\BackendUserAuthentication::getFilePermissionsForStorage
    TYPO3\CMS\Core\Authentication\BackendUserAuthentication::getFilePermissionsForStorage was removed in typo3/cms-core v13.0.0 packagist.org

And 1,166 more in this version.

v12.0.0

1,040 breaking changes, first published October 4, 2022.

  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__get
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__get was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__isset
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__isset was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__set
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__set was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__unset
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::__unset was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::createSessionId
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::createSessionId was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::fetchUserSession
    TYPO3\CMS\Core\Authentication\AbstractUserAuthentication::fetchUserSession was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\BackendUserAuthentication::hasEditAccessToLiveWorkspace
    TYPO3\CMS\Core\Authentication\BackendUserAuthentication::hasEditAccessToLiveWorkspace was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\Mfa\MfaProviderInterface
    TYPO3\CMS\Core\Authentication\Mfa\MfaProviderInterface was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\Mfa\MfaProviderPropertyManager
    TYPO3\CMS\Core\Authentication\Mfa\MfaProviderPropertyManager was removed in typo3/cms-core v12.0.0 packagist.org
  • Removed TYPO3\CMS\Core\Authentication\Mfa\MfaViewType
    TYPO3\CMS\Core\Authentication\Mfa\MfaViewType was removed in typo3/cms-core v12.0.0 packagist.org

And 1,030 more in this version.

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