TCAdefaults

This allows default values of TCA fields that are available for various TCA column types to be set or overridden, for instance for type=input.

Default values can be set at the type level: TCAdefaults.[table name].[field].types.[type] or field level: TCAdefaults.[table name].[field]

This key is also available at the Page TSconfig level. The order that default values are set when creating new records in the backend is this:

1. Database field default value
2. Value from $GLOBALS['TCA']
3. Field-level ref:user TSconfig <userTsTcaDefaults>
4. Type-level ref:user TSconfig <userTsTcaDefaults>
5. Field-level TCAdefaults configuration
6. Type-level TCAdefaults configuration
7. Value from "defVals" GET variables
8. Value from previous record based on useColumnsForDefaultValues

However, the order for default values used by the \TYPO3\CMS\Core\DataHandling\DataHandler if a particular field is inaccessible to a user will be:

1. Value from $GLOBALS['TCA']
2. Value from User TSconfig (these settings)

So these will be the values that are set if the user has no access to the field anyway.

Example:

# Show newly created pages by default
TCAdefaults.pages.hidden = 0

'ctrl' => [
  'useColumnsForDefaultValues' => 'doktype,fe_group,hidden',
  ...
]

If 'hidden' is in the list, it gets overridden with the "neighbor" record value (see \TYPO3\CMS\Backend\Form\FormDataProvider\DatabaseRowInitializeNew::setDefaultsFromNeighborRow) and as the value is set - usually to '0' - it will not be overridden again. To make it work as expected, that value must be overridden. This can be done for example in the Configuration/TCA/Overrides folder of an extension:

$GLOBALS['TCA']['pages']['ctrl']['useColumnsForDefaultValues'] = 'doktype,fe_group';

TCAdefaults.tt_content {
    header_layout = 1
    # Use specific default values for certain types
    header_layout.types {
        textmedia = 3
        image = 2
    }
}