[TYPO3-dam] categories_mm_config

[Stephan Petzl]

hello,

i want to add a "add" symbol to the category field.
can you tell me what the "categories_mm_config" parameter is for:

TCA:
'category' => array (
			'label' => 'LLL:EXT:dam/locallang_db.php:tx_dam_item.category',
			'l10n_mode' => 'exclude',
			'l10n_display' => 'defaultAsReadonly',
			'config' => 
$GLOBALS['T3_VAR']['ext']['dam']['TCA']['categories_mm_config'],
		),

why is there no possibility to add categories by default?

BR Stef