Feature: #109412 - Auto-discovery of form YAML configurations 

Directory layout 

EXT:my_extension/
  Configuration/
    Form/
      MyFormSet/
        config.yaml

The sub-directory name (MyFormSet) is arbitrary. An extension may ship multiple sets in separate sub-directories.

The config.yaml 

Contains both the set metadata and the actual form configuration in a single file. The metadata keys (name, label, priority) are reserved; all other keys are treated as form configuration (prototype definitions, form elements, validators, finishers, rendering options etc.).

# Unique identifier, vendor/name convention (like composer package names)
name: my-vendor/my-form-set

# Human-readable label for diagnostic output
label: 'My Custom Form Set'

# Load order: lower values are loaded first and act as base configuration.
# Extension sets should use a value > 10 to be merged on top of the
# TYPO3 core base set (typo3/form-base, priority: 10).
# Default: 100
priority: 200

# Form configuration follows directly below the metadata:
persistenceManager:
  allowedExtensionPaths:
    10: 'EXT:my_extension/Resources/Private/Forms/'

Priority and merge order 

Sets are sorted by ascending priority (lower = loaded first = acts as base, higher = override). Each set's configuration is merged on top of the previous one using array_replace_recursive, identical to how the former TypoScript mechanism worked.

Migration from TypoScript registration 

Before TYPO3 v14.2, YAML files had to be registered explicitly via TypoScript:

plugin.tx_form.settings.yamlConfigurations {
    1732785702 = EXT:my_extension/Configuration/Form/MySetup.yaml
}

# Backend had to be registered separately:
module.tx_form.settings.yamlConfigurations {
    1732785703 = EXT:my_extension/Configuration/Form/MySetup.yaml
}

This registration mechanism has been deprecated and will be removed in TYPO3 v15.0. See Deprecation-109412 for details.

After the migration:

1. Create the directory EXT:my_extension/Configuration/Form/MySet/.
2. Create config.yaml with name, optionally priority, and the form configuration directly in the same file.
3. Remove the TypoScript registrations from setup.typoscript.

name: my-vendor/my-form-set
label: 'My Custom Form Set'
priority: 200

# Form configuration (formerly your MySetup.yaml content) goes here:
prototypes:
  standard:
    formElementsDefinition:
      ...

Disabling a form set 

Because all sets from all active extensions are loaded automatically, a mechanism exists to opt out of specific sets without modifying the extension that provides them.

To disable a set, add its declared name (from config.yaml) to $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['form']['disabledSets'] in ext_localconf.php or config/system/settings.php:

// Disable a third-party form set that conflicts with the site configuration:
$GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['form']['disabledSets'][]
    = 'some-vendor/conflicting-set';

The matching is done against the name field in config.yaml, not against the directory name, so renaming the set directory does not break an existing disable list.

EXT:form base set 

The TYPO3 Form Framework ships its own base set at EXT:form/Configuration/Form/Base/ (typo3/form-base, priority 10). All validators, form elements, finishers and shared rendering configuration are defined directly in EXT:form/Configuration/Form/Base/config.yaml.