diff --git a/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php b/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php
index 5d45a1270c62cb8e0cd17a1400350b59cd04aad5..1a96445b11d558bfd939c49491d4090232d09b10 100644
--- a/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php
+++ b/typo3/sysext/backend/Classes/Form/FormDataProvider/AbstractItemProvider.php
@@ -943,6 +943,7 @@ abstract class AbstractItemProvider
         $foreignTableClauseArray = $this->processForeignTableClause($result, $foreignTableName, $localFieldName);
 
         $fieldList = BackendUtility::getCommonSelectFields($foreignTableName, $foreignTableName . '.');
+        /** @var QueryBuilder $queryBuilder */
         $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
             ->getQueryBuilderForTable($foreignTableName);
 
@@ -956,7 +957,7 @@ abstract class AbstractItemProvider
             ->where($foreignTableClauseArray['WHERE']);
 
         if (!empty($foreignTableClauseArray['GROUPBY'])) {
-            $queryBuilder->groupBy($foreignTableClauseArray['GROUPBY']);
+            $queryBuilder->groupBy(...$foreignTableClauseArray['GROUPBY']);
         }
 
         if (!empty($foreignTableClauseArray['ORDERBY'])) {
diff --git a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectItemsTest.php b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectItemsTest.php
index b577626a224b2767a78cda7e6f8dd0679ba2b10c..feba4515c43c9863d4cc6735b341b232401405d4 100644
--- a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectItemsTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectItemsTest.php
@@ -1754,7 +1754,7 @@ class TcaSelectItemsTest extends \TYPO3\TestingFramework\Core\Unit\UnitTestCase
                             'foreign_table' => 'fTable',
                             'foreign_table_where' => '
                                 AND ftable.uid=1
-                                GROUP BY groupField
+                                GROUP BY groupField1, groupField2
                                 ORDER BY orderField
                                 LIMIT 1,2',
                         ],
@@ -1779,7 +1779,7 @@ class TcaSelectItemsTest extends \TYPO3\TestingFramework\Core\Unit\UnitTestCase
         $queryBuilderProphet->select('fTable.uid')->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
         $queryBuilderProphet->from('fTable')->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
         $queryBuilderProphet->from('pages')->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
-        $queryBuilderProphet->groupBy(['groupField'])->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
+        $queryBuilderProphet->groupBy('groupField1', 'groupField2')->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
         $queryBuilderProphet->addOrderBy('orderField', null)->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
         $queryBuilderProphet->setFirstResult(1)->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());
         $queryBuilderProphet->setMaxResults(2)->shouldBeCalled()->willReturn($queryBuilderProphet->reveal());