TYPO3 TCA selectMultipleSideBySide删除可用的项目

Question

I want to create a TCA with selectMultipleSideBySide renderType and save the selected items in a column (maybe the uids?)

What I expect: Click on an available item -> it moves to the left side to the selecteted items. Select another available item -> it appears also on the left side. If I delete a selected item -> it moves back to the available items.

What I get: Select a available item -> it moves to selected items. Select another available item -> it appears on selected items BUT the item before disappears on both sides.

My TCA:

    \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addTCAcolumns('tt_content', array(
        'tx_vend_items' => array(
            'exclude' => 1,
            'label' => 'Items',
            'l10n_mode' => 'exclude',
            'config' => array(
                'type' => 'select',
                'size' => 5,
                'renderType' => 'selectMultipleSideBySide',
                'enableMultiSelectFilterTextfield' => true,
                'itemsProcFunc' => \Vend\Ext\Hooks\Backend\Preview\Renderer::class . '->getTest',
            )
        ),
    ));

getTest()

    public function getTest(&$pa)
    {
        for ($i = 0; $i < 10; $i++) {
            $pa['items'][] = [
                "Var: " . $i,
                1 * $i,
            ];
        }
    }

Did I miss something? Also to save the selected items

Answer 1

I added

 'minitems' => 0,
 'maxitems' => 99999,

to my TCA and now it works