TYPO3 Core

This feature is missing in TYPO3 7.6.2.
The LOADED condition is not considered at all. The TYPO3 Backend (TCE) uses the foreign_table relation even if the demanded extension has not been installed.

field taxcat_id:
  config foreign_table: static_tax_categories
  displayCond    EXT:static_info_tables_taxes:LOADED:true

This raises a TYPO3 exception.

Uncaught TYPO3 Exception
    #1439569743: Field taxcat_id of table tt_products reference to foreign table static_tax_categories, but this table is not defined in TCA (More information)
    UnexpectedValueException thrown in file    /var/www/html/developer/typo3_src-7.6.2/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php in line 895.
    16 TYPO3\CMS\Backend\Form\FormDataProvider\AbstractItemProvider::buildForeignTableQuery(array, "taxcat_id")    /var/www/html/developer/typo3_src-7.6.2/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php:
    00417: 
    00418:         $foreignTable = $result['processedTca']['columns'][$fieldName]['config']['foreign_table'];
    00419:         $foreignTableQueryArray = $this->buildForeignTableQuery($result, $fieldName);
    00420:         $queryResource = $database->exec_SELECT_queryArray($foreignTableQueryArray);
    00421: 
    15 TYPO3\CMS\Backend\Form\FormDataProvider\AbstractItemProvider::addItemsFromForeignTable(array, "taxcat_id", array)    /var/www/html/developer/typo3_src-7.6.2/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaSelectTreeItems.php:
    00054:             $staticItems = $fieldConfig['config']['items'];
    00055: 
    00056:             $fieldConfig['config']['items'] = $this->addItemsFromForeignTable($result, $fieldName, $fieldConfig['config']['items']);
    00057:             $dynamicItems = array_diff_key($fieldConfig['config']['items'], $staticItems);
    00058: