Breaking: #109849 - Removed "buildFormDefinitionValidationConfiguration" hook 

See forge#109849

Description 

The hook $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['ext/form']['buildFormDefinitionValidationConfiguration'] has been removed in favor of the new PSR-14 event \TYPO3\CMS\Form\Event\AfterFormDefinitionValidationConfigurationIsBuiltEvent .

Impact 

Any hook implementation registered under this identifier will no longer be executed.

Affected installations 

TYPO3 installations with custom extensions that register a hook class under $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['ext/form']['buildFormDefinitionValidationConfiguration'] are affected.

Migration 

The hook has been removed without a deprecation phase to allow extensions to remain compatible with both TYPO3 v14 (using the hook) and v15+ (using the new event). Implementing the PSR-14 event provides the same or greater control.

Use the AfterFormDefinitionValidationConfigurationIsBuiltEvent to achieve the same functionality with the new event-based system.