Extension builder overwrite fe_user TCA - typo3

Question

If I try to extend fe_user table by creating a new Model Object on extension builder in Typo3 6.1.7, it overwrites TCA by writing those lines in ext_tables.php of my extension:
\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addLLrefForTCAdescr('fe_users', 'EXT:voiwizard/Resources/Private/Language/locallang_csh_fe_users.xlf');
\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::allowTableOnStandardPages('fe_users');
$TCA['fe_users'] = array(
'ctrl' => array(
'title' => 'LLL:EXT:voiwizard/Resources/Private/Language/locallang_db.xlf:fe_users',
'label' => 'prova',
'tstamp' => 'tstamp',
'crdate' => 'crdate',
'cruser_id' => 'cruser_id',
'dividers2tabs' => TRUE,
'versioningWS' => 2,
'versioning_followPages' => TRUE,
'origUid' => 't3_origuid',
'languageField' => 'sys_language_uid',
'transOrigPointerField' => 'l10n_parent',
'transOrigDiffSourceField' => 'l10n_diffsource',
'delete' => 'deleted',
'enablecolumns' => array(
'disabled' => 'hidden',
'starttime' => 'starttime',
'endtime' => 'endtime',
),
'searchFields' => 'prova,',
'dynamicConfigFile' => \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::extPath($_EXTKEY) . 'Configuration/TCA/User.php',
'iconfile' => \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::extRelPath($_EXTKEY) . 'Resources/Public/Icons/fe_users.gif'
),
);
This code overwrites the original fe_users's TCA configuration and the back-end [website user][1] table becomes inaccessible.
Is there any way to prevent this or do I have to delete those lines every time I want to save the changes in the extension builder?

Answer 1

I've found an error in my relationship:
To properly extend fe_users table with a Model Object in Extension Builder, I had to "extend existing model class" \TYPO3\CMS\Extbase\Domain\Model\FrontendUser instead of "map to existing table" fe_users.
In this way, everything works as expected!