ext_tables.php

<?php

if (!defined('TYPO3_MODE')) {
    die('Access denied.');
}

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
    $_EXTKEY,
    'Map',
    'Smart Map'
);

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addStaticFile($_EXTKEY, 'Configuration/TypoScript', 'Smart Map');

/*
* Register FlexForms
*/
$extensionName = strtolower(\TYPO3\CMS\Core\Utility\GeneralUtility::underscoredToUpperCamelCase($_EXTKEY));
$pluginNames = array(
    'map',
);

foreach ($pluginNames as $pluginName) {
    $pluginSignature = $extensionName.'_'.$pluginName;
    $TCA['tt_content']['types']['list']['subtypes_addlist'][$pluginSignature] = 'pi_flexform';

    \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addPiFlexFormValue(
        $pluginSignature,
        'FILE:EXT:'.$_EXTKEY.'/Configuration/FlexForms/'.$pluginName.'.xml'
    );
}