ext_tables.php

<?php

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

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
    $_EXTKEY,
    'Owlslider',
    'owlSlider'
);

$pluginSignature = str_replace('_', '', $_EXTKEY) . '_owlslider';

$TCA['tt_content']['types']['list']['subtypes_addlist'][$pluginSignature] = 'pi_flexform';

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

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

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addLLrefForTCAdescr(
    'tx_owlslider_domain_model_item',
    'EXT:owl_slider/Resources/Private/Language/locallang_csh_tx_owlslider_domain_model_item.xlf'
);

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::allowTableOnStandardPages(
    'tx_owlslider_domain_model_item'
);

include_once(\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::extPath($_EXTKEY) . 'Classes/PHP/tx_owlslider_addFieldsToFlexForm.php');

?>