diff --git a/.github/phpunit.functional.xml b/.github/phpunit.functional.xml
new file mode 100644
index 0000000..d1fa385
--- /dev/null
+++ b/.github/phpunit.functional.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" colors="true" cacheResult="false" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.5/phpunit.xsd" bootstrap="../vendor/typo3/testing-framework/Resources/Core/Build/FunctionalTestsBootstrap.php">
+    <source>
+        <include>
+            <directory>../Classes/</directory>
+        </include>
+    </source>
+    <testsuites>
+        <testsuite name="functional">
+            <directory suffix=".php">../Tests/Functional/</directory>
+            <exclude>../Tests/Functional/Fixtures/</exclude>
+        </testsuite>
+    </testsuites>
+    <php>
+        <const name="TYPO3_TESTING_FUNCTIONAL_REMOVE_ERROR_HANDLER" value="true"/>
+        <ini name="display_errors" value="1"/>
+        <env name="TYPO3_CONTEXT" value="Testing"/>
+    </php>
+</phpunit>
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index db07d6e..55d845f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,6 +17,31 @@ jobs:
           bootstrap: vendor/autoload.php
           configuration: .github/phpunit.xml
 
+  functional-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: '8.4'
+          extensions: mbstring, intl, pdo_sqlite
+          tools: composer:v2
+
+      - name: Composer install
+        run: composer install --ignore-platform-reqs --no-interaction
+
+      - name: Prepare TYPO3 extension path
+        run: |
+          mkdir -p public/typo3conf/ext/
+          if [ ! -L public/typo3conf/ext/webcomponents ]; then ln -snvf ../../../. public/typo3conf/ext/webcomponents; fi
+
+      - name: Functional Tests
+        env:
+          typo3DatabaseDriver: pdo_sqlite
+          typo3DatabaseName: typo3
+        run: vendor/bin/phpunit -c .github/phpunit.functional.xml
+
   phpstan:
     runs-on: ubuntu-latest
     steps:
diff --git a/Classes/DataProviding/Helpers/InlineItemsHelper.php b/Classes/DataProviding/Helpers/InlineItemsHelper.php
index c5b522f..6814534 100644
--- a/Classes/DataProviding/Helpers/InlineItemsHelper.php
+++ b/Classes/DataProviding/Helpers/InlineItemsHelper.php
@@ -8,7 +8,6 @@
 use TYPO3\CMS\Core\Context\Context;
 use TYPO3\CMS\Core\Database\Connection;
 use TYPO3\CMS\Core\Database\ConnectionPool;
-use TYPO3\CMS\Core\Database\Query\QueryHelper;
 use TYPO3\CMS\Core\Domain\Repository\PageRepository;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 
@@ -25,49 +24,55 @@ public function __construct(
     ) {}
 
     /**
-     * @param array<string, string|integer> $parentRecord
-     * @return list<array<string, string|integer>>
+     * @param array<string, int|string> $parentRecord
+     * @return list<array<string, int|string>>
      */
     public function loadInlineItems(array $parentRecord, string $inlineFieldName, string $parentTable = 'tt_content'): array
     {
         // if the field is empty, and we're not in a workspace context, then there are no inline items
-        /** @var int|string $versioningWorkspaceId */
-        $versioningWorkspaceId = $this->context->getPropertyFromAspect('workspace', 'id');
-        $versioningWorkspaceId = (int)$versioningWorkspaceId;
+        $workspaceId = $this->context->getPropertyFromAspect('workspace', 'id');
+        $versioningWorkspaceId = is_int($workspaceId) || is_string($workspaceId) ? (int)$workspaceId : 0;
         if (empty($parentRecord[$inlineFieldName]) && $versioningWorkspaceId === 0) {
             return [];
         }
 
         $inlineFieldTca = $this->getInlineFieldTca($inlineFieldName, $parentTable);
-        $foreignTable = $inlineFieldTca['config']['foreign_table'] ?? null;
-        if ($foreignTable === null) {
+        $inlineFieldConfig = $inlineFieldTca['config'] ?? [];
+        $foreignTable = $inlineFieldConfig['foreign_table'] ?? null;
+        if (!is_string($foreignTable) || $foreignTable === '') {
             throw new \Exception(
                 sprintf('Could not load inline items for field "%s". Missing \'foreign_table\' in its TCA configuration', $inlineFieldName),
                 1686299043
             );
         }
-        $foreignField = $inlineFieldTca['config']['foreign_field'] ?? null;
-        $foreignTableTca = $GLOBALS['TCA'][$foreignTable];
-        $foreignSortby = $inlineFieldTca['config']['foreign_sortby'] ?? $foreignTableTca['ctrl']['sortby'] ?? null;
+        $foreignField = $inlineFieldConfig['foreign_field'] ?? null;
+        if (!is_string($foreignField) || $foreignField === '') {
+            $foreignField = null;
+        }
+        $foreignTableTca = $GLOBALS['TCA'][$foreignTable] ?? [];
+        $foreignSortby = $inlineFieldConfig['foreign_sortby'] ?? $foreignTableTca['ctrl']['sortby'] ?? null;
+        if (!is_string($foreignSortby) || $foreignSortby === '') {
+            $foreignSortby = null;
+        }
         $queryBuilder = $this->connectionPool->getQueryBuilderForTable($foreignTable);
         $queryBuilder->getRestrictions()->removeAll();
 
         $parentRecordId = $parentRecord['_LOCALIZED_UID'] ?? $parentRecord['uid'] ?? 0;
-        $constraints = [];
+        $constraints = $this->pageRepository->getDefaultConstraints($foreignTable);
         if (!empty($foreignField)) {
-            $constraints[] = $queryBuilder->expr()->eq($foreignField, $queryBuilder->createNamedParameter($parentRecordId, Connection::PARAM_INT));
+            $constraints['foreign_field'] = $queryBuilder->expr()->eq($foreignField, $queryBuilder->createNamedParameter($parentRecordId, Connection::PARAM_INT));
         } else {
             $itemsUidList = GeneralUtility::intExplode(',', (string)($parentRecord[$inlineFieldName] ?? ''), true);
             if (empty($itemsUidList)) {
                 return [];
             }
-            $constraints[] = $queryBuilder->expr()->in('uid', $queryBuilder->createNamedParameter($itemsUidList, ArrayParameterType::INTEGER));
+            $constraints['uidList'] = $queryBuilder->expr()->in('uid', $queryBuilder->createNamedParameter($itemsUidList, ArrayParameterType::INTEGER));
         }
-        if (isset($foreignTableTca['ctrl']['languageField'])) {
-            $constraints[] = $queryBuilder->expr()->in($foreignTableTca['ctrl']['languageField'], $queryBuilder->createNamedParameter([-1, $parentRecord['sys_language_uid'] ?? 0], ArrayParameterType::INTEGER));
+        $languageField = $foreignTableTca['ctrl']['languageField'] ?? null;
+        if (is_string($languageField) && $languageField !== '') {
+            $constraints['language'] = $queryBuilder->expr()->in($languageField, $queryBuilder->createNamedParameter([-1, $parentRecord['sys_language_uid'] ?? 0], ArrayParameterType::INTEGER));
         }
-        $constraints[] = QueryHelper::stripLogicalOperatorPrefix($this->pageRepository->enableFields($foreignTable));
-        $queryBuilder->select('*')->from($foreignTable)->where(...$constraints);
+        $queryBuilder->select('*')->from($foreignTable)->where(...array_values($constraints));
         if ($foreignSortby) {
             $queryBuilder->orderBy($foreignSortby);
         }
@@ -96,7 +101,7 @@ public function loadInlineItems(array $parentRecord, string $inlineFieldName, st
     }
 
     /**
-     * @return array{config: array{foreign_table?: string, foreign_field?: string, foreign_sortby?: string}, label: string, type: string}
+     * @return array{config?: array<string, mixed>}
      */
     protected function getInlineFieldTca(string $inlineFieldName, string $localTableName = 'tt_content'): array
     {
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItems.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItems.csv
new file mode 100644
index 0000000..e86d597
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItems.csv
@@ -0,0 +1,8 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1","sorting"
+,"1","1","1","tx_inlineitemshelperfixture_parent","-1","BJB","2"
+,"2","1","1","tx_inlineitemshelperfixture_parent","-1","BJB","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspace.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspace.csv
new file mode 100644
index 0000000..919e747
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspace.csv
@@ -0,0 +1,8 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1","t3ver_wsid","t3ver_state","sorting"
+,"1","1","1","tx_inlineitemshelperfixture_parent","-1","BJB","1","1","2"
+,"2","1","1","tx_inlineitemshelperfixture_parent","-1","BJB","1","1","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheBeginning.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheBeginning.csv
new file mode 100644
index 0000000..bc47cd6
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheBeginning.csv
@@ -0,0 +1,9 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","input_1","t3ver_wsid","t3ver_state","sorting"
+,"1","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","2"
+,"2","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","3"
+,"3","1","1","tx_inlineitemshelperfixture_parent","BJB","1","1","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheEnd.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheEnd.csv
new file mode 100644
index 0000000..f6affcb
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheEnd.csv
@@ -0,0 +1,9 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","input_1","t3ver_wsid","t3ver_state","sorting"
+,"1","1","1","1","-1","BJB","0","0","2"
+,"2","1","1","1","-1","BJB","0","0","3"
+,"3","1","1","1","-1","BJB","1","1","4"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemInTheMiddle.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemInTheMiddle.csv
new file mode 100644
index 0000000..dda6ee5
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemInTheMiddle.csv
@@ -0,0 +1,9 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","input_1","t3ver_wsid","t3ver_state","sorting"
+,"1","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","2"
+,"2","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","5"
+,"3","1","1","tx_inlineitemshelperfixture_parent","BJB","1","1","4"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithRemovedItem.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithRemovedItem.csv
new file mode 100644
index 0000000..64c6aa0
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsInWorkspaceWithRemovedItem.csv
@@ -0,0 +1,9 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","input_1","t3ver_wsid","t3ver_state","t3ver_oid","sorting"
+,"1","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","0","3"
+,"2","1","1","tx_inlineitemshelperfixture_parent","BJB","0","0","0","2"
+,"3","1","1","tx_inlineitemshelperfixture_parent","BJB","1","2","1","3"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsRearrangedInWorkspace.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsRearrangedInWorkspace.csv
new file mode 100644
index 0000000..26479bc
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/MultipleInlineItemsRearrangedInWorkspace.csv
@@ -0,0 +1,10 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1","sorting","t3ver_oid","t3ver_wsid"
+,"1","1","1","1","-1","BJB/first","1","0","0"
+,"2","1","1","1","-1","BJB/second","2","0","0"
+,"3","1","1","1","-1","BJB/first","2","1","1"
+,"4","1","1","1","-1","BJB/second","1","2","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItem.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItem.csv
new file mode 100644
index 0000000..46db3b3
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItem.csv
@@ -0,0 +1,7 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1"
+,"1","1","1","tx_inlineitemshelperfixture_parent","-1","BJB"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemChangedInWorkspace.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemChangedInWorkspace.csv
new file mode 100644
index 0000000..f21a2ed
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemChangedInWorkspace.csv
@@ -0,0 +1,8 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1","t3ver_wsid","t3ver_state","t3ver_oid"
+,"1","1","1","tx_inlineitemshelperfixture_parent","-1","BJB","0","0","0"
+,"2","1","1","tx_inlineitemshelperfixture_parent","-1","BJB/changed","1","0","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemEnabledInWorkspace.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemEnabledInWorkspace.csv
new file mode 100644
index 0000000..b0fc83e
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemEnabledInWorkspace.csv
@@ -0,0 +1,8 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","hidden","t3ver_wsid","t3ver_state","t3ver_oid"
+,"1","1","1","1","-1","1","0","0","0"
+,"2","1","1","1","-1","0","1","0","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemInWorkspace.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemInWorkspace.csv
new file mode 100644
index 0000000..97c3457
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemInWorkspace.csv
@@ -0,0 +1,7 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1","t3ver_wsid","t3ver_state"
+,"1","1","1","1","-1","BJB","1","1"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemWithoutDefaultTranslation.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemWithoutDefaultTranslation.csv
new file mode 100644
index 0000000..9680443
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/OneInlineItemWithoutDefaultTranslation.csv
@@ -0,0 +1,7 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1"
+,"1","1","2","tx_inlineitemshelperfixture_parent","1","BJB"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/Fixtures/TranslatedInlineItem.csv b/Tests/Functional/DataProviding/Helpers/Fixtures/TranslatedInlineItem.csv
new file mode 100644
index 0000000..394a7da
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/Fixtures/TranslatedInlineItem.csv
@@ -0,0 +1,8 @@
+"tx_inlineitemshelperfixture_child"
+,"uid","pid","parentid","parenttable","sys_language_uid","input_1"
+,"1","1","1","tx_inlineitemshelperfixture_parent","0","BJB"
+,"2","1","2","tx_inlineitemshelperfixture_parent","1","BJB/overlaid"
+
+"tx_inlineitemshelperfixture_parent"
+,"uid"
+,"1"
diff --git a/Tests/Functional/DataProviding/Helpers/InlineItemsHelperTest.php b/Tests/Functional/DataProviding/Helpers/InlineItemsHelperTest.php
new file mode 100644
index 0000000..68e0e7f
--- /dev/null
+++ b/Tests/Functional/DataProviding/Helpers/InlineItemsHelperTest.php
@@ -0,0 +1,276 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Sinso\Webcomponents\Tests\Functional\DataProviding\Helpers;
+
+use Sinso\Webcomponents\DataProviding\Helpers\InlineItemsHelper;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use TYPO3\CMS\Core\Context\Context;
+use TYPO3\CMS\Core\Context\WorkspaceAspect;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Domain\Repository\PageRepository;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\TestingFramework\Core\Functional\FunctionalTestCase;
+
+#[CoversClass(InlineItemsHelper::class)]
+final class InlineItemsHelperTest extends FunctionalTestCase
+{
+    private const string INLINE_FIELD = 'inline_2';
+    private const string PARENT_TABLE = 'tx_inlineitemshelperfixture_parent';
+    private const string CHILD_TABLE = 'tx_inlineitemshelperfixture_child';
+
+    private InlineItemsHelper $subject;
+
+    protected array $testExtensionsToLoad = [
+        __DIR__ . '/../../Fixtures/Extensions/inline_items_helper_fixture',
+        'typo3conf/ext/webcomponents',
+    ];
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->setWorkspace(0);
+        $this->subject = new InlineItemsHelper(
+            $this->get(ConnectionPool::class),
+            $this->get(Context::class),
+            $this->get(PageRepository::class),
+        );
+    }
+
+    #[Test]
+    public function returnsEmptyArrayForNoData(): void
+    {
+        $items = $this->subject->loadInlineItems(['pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertSame([], $items);
+    }
+
+    #[Test]
+    public function returnsEmptyArrayForNoDataInWorkspace(): void
+    {
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertSame([], $items);
+    }
+
+    #[Test]
+    public function returnsOneItemForOneRecordInDatabase(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItem.csv');
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1, self::INLINE_FIELD => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(1, $items);
+        self::assertIsArray($items[0]);
+    }
+
+    #[Test]
+    public function returnsRecordFromDatabase(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItem.csv');
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1, self::INLINE_FIELD => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        $connection = $this->getConnectionPool()->getConnectionForTable(self::CHILD_TABLE);
+        $rows = $connection->executeQuery(
+            'SELECT * FROM ' . self::CHILD_TABLE . ' WHERE parentid = :parentid',
+            ['parentid' => 1]
+        )->fetchAllAssociative();
+
+        self::assertIsArray($items);
+        self::assertCount(1, $items);
+        self::assertSame($rows, $items);
+    }
+
+    #[Test]
+    public function returnsSortedItems(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItems.csv');
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1, self::INLINE_FIELD => 2], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(2, $items);
+        self::assertSame(2, $items[0]['uid']);
+        self::assertSame(1, $items[1]['uid']);
+    }
+
+    #[Test]
+    public function returnsOneItemWithOneRecordCreatedInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItemInWorkspace.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(1, $items);
+        self::assertIsArray($items[0]);
+    }
+
+    #[Test]
+    public function returnSortedItemsInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsInWorkspace.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(2, $items);
+        self::assertSame(2, $items[0]['uid']);
+        self::assertSame(1, $items[1]['uid']);
+    }
+
+    #[Test]
+    public function returnSortedItemsWithCreatedOneAtTheBeginningInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheBeginning.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(3, $items);
+        self::assertSame(3, $items[0]['uid']);
+        self::assertSame(1, $items[1]['uid']);
+        self::assertSame(2, $items[2]['uid']);
+    }
+
+    #[Test]
+    public function returnSortedItemsWithCreatedOneInTheMiddleInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemInTheMiddle.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(3, $items);
+        self::assertSame(1, $items[0]['uid']);
+        self::assertSame(3, $items[1]['uid']);
+        self::assertSame(2, $items[2]['uid']);
+    }
+
+    #[Test]
+    public function returnSortedItemsWithCreatedOneAtTheEndInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsInWorkspaceWithNewItemAtTheEnd.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(3, $items);
+        self::assertSame(1, $items[0]['uid']);
+        self::assertSame(2, $items[1]['uid']);
+        self::assertSame(3, $items[2]['uid']);
+    }
+
+    #[Test]
+    public function returnSortedItemsWithRemovedItemInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsInWorkspaceWithRemovedItem.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(1, $items);
+        self::assertSame(2, $items[0]['uid']);
+    }
+
+    #[Test]
+    public function returnsItemChangedInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItemChangedInWorkspace.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(1, $items);
+        self::assertSame('BJB/changed', $items[0]['input_1']);
+    }
+
+    #[Test]
+    public function returnsSortedItemsWithSortingChangedInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/MultipleInlineItemsRearrangedInWorkspace.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertIsArray($items);
+        self::assertCount(2, $items);
+        self::assertSame('BJB/second', $items[0]['input_1']);
+        self::assertSame('BJB/first', $items[1]['input_1']);
+    }
+
+    #[Test]
+    public function returnsItemEnabledInWorkspace(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItemEnabledInWorkspace.csv');
+
+        $this->setWorkspace(1);
+
+        $items = $this->subject->loadInlineItems(['uid' => 1, 'pid' => 1], self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertCount(1, $items);
+    }
+
+    #[Test]
+    public function returnsOverlaidItemWhenParentRecordIsTranslated(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/TranslatedInlineItem.csv');
+        $record = [
+            'uid' => 1,
+            'pid' => 1,
+            'sys_language_uid' => 1,
+            self::INLINE_FIELD => 1,
+            '_LOCALIZED_UID' => 2,
+        ];
+
+        $items = $this->subject->loadInlineItems($record, self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertCount(1, $items);
+        self::assertSame('BJB/overlaid', $items[0]['input_1']);
+    }
+
+    #[Test]
+    public function returnsItemWithoutDefaultTranslationWhenContentElementIsTranslated(): void
+    {
+        $this->importCSVDataSet(__DIR__ . '/Fixtures/OneInlineItemWithoutDefaultTranslation.csv');
+        $record = [
+            'uid' => 1,
+            'pid' => 1,
+            'sys_language_uid' => 1,
+            self::INLINE_FIELD => 1,
+            '_LOCALIZED_UID' => 2,
+        ];
+
+        $items = $this->subject->loadInlineItems($record, self::INLINE_FIELD, self::PARENT_TABLE);
+
+        self::assertCount(1, $items);
+        self::assertSame('BJB', $items[0]['input_1']);
+    }
+
+    private function setWorkspace(int $workspaceId): void
+    {
+        $context = GeneralUtility::makeInstance(Context::class);
+        $context->setAspect('workspace', new WorkspaceAspect($workspaceId));
+    }
+}
diff --git a/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_child.php b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_child.php
new file mode 100644
index 0000000..0d0b9b1
--- /dev/null
+++ b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_child.php
@@ -0,0 +1,46 @@
+<?php
+
+return [
+    'ctrl' => [
+        'title' => 'InlineItemsHelper fixture child',
+        'label' => 'input_1',
+        'tstamp' => 'tstamp',
+        'crdate' => 'crdate',
+        'delete' => 'deleted',
+        'sortby' => 'sorting',
+        'versioningWS' => true,
+        'languageField' => 'sys_language_uid',
+        'transOrigPointerField' => 'l10n_parent',
+        'transOrigDiffSourceField' => 'l10n_diffsource',
+        'translationSource' => 'l10n_source',
+        'enablecolumns' => [
+            'disabled' => 'hidden',
+        ],
+        'security' => [
+            'ignorePageTypeRestriction' => true,
+        ],
+    ],
+    'columns' => [
+        'parentid' => [
+            'config' => [
+                'type' => 'passthrough',
+            ],
+        ],
+        'parenttable' => [
+            'config' => [
+                'type' => 'passthrough',
+            ],
+        ],
+        'input_1' => [
+            'label' => 'Input',
+            'config' => [
+                'type' => 'input',
+            ],
+        ],
+    ],
+    'types' => [
+        '0' => [
+            'showitem' => 'input_1',
+        ],
+    ],
+];
diff --git a/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_parent.php b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_parent.php
new file mode 100644
index 0000000..7f4da08
--- /dev/null
+++ b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/Configuration/TCA/tx_inlineitemshelperfixture_parent.php
@@ -0,0 +1,39 @@
+<?php
+
+return [
+    'ctrl' => [
+        'title' => 'InlineItemsHelper fixture parent',
+        'label' => 'uid',
+        'tstamp' => 'tstamp',
+        'crdate' => 'crdate',
+        'delete' => 'deleted',
+        'sortby' => 'sorting',
+        'versioningWS' => true,
+        'languageField' => 'sys_language_uid',
+        'transOrigPointerField' => 'l10n_parent',
+        'transOrigDiffSourceField' => 'l10n_diffsource',
+        'translationSource' => 'l10n_source',
+        'enablecolumns' => [
+            'disabled' => 'hidden',
+        ],
+        'security' => [
+            'ignorePageTypeRestriction' => true,
+        ],
+    ],
+    'columns' => [
+        'inline_2' => [
+            'label' => 'Inline items',
+            'config' => [
+                'type' => 'inline',
+                'foreign_table' => 'tx_inlineitemshelperfixture_child',
+                'foreign_field' => 'parentid',
+                'foreign_table_field' => 'parenttable',
+            ],
+        ],
+    ],
+    'types' => [
+        '0' => [
+            'showitem' => 'inline_2',
+        ],
+    ],
+];
diff --git a/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/composer.json b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/composer.json
new file mode 100644
index 0000000..98e1271
--- /dev/null
+++ b/Tests/Functional/Fixtures/Extensions/inline_items_helper_fixture/composer.json
@@ -0,0 +1,11 @@
+{
+  "name": "julius-baer/inline-items-helper-fixture",
+  "type": "typo3-cms-extension",
+  "description": "Functional test fixture extension for InlineItemsHelper",
+  "version": "1.0.0",
+  "extra": {
+    "typo3/cms": {
+      "extension-key": "inline_items_helper_fixture"
+    }
+  }
+}
diff --git a/Tests/Unit/DataProviding/Helpers/InlineItemsHelperTest.php b/Tests/Unit/DataProviding/Helpers/InlineItemsHelperTest.php
new file mode 100644
index 0000000..31c4d5e
--- /dev/null
+++ b/Tests/Unit/DataProviding/Helpers/InlineItemsHelperTest.php
@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Sinso\Webcomponents\Tests\Unit\DataProviding\Helpers;
+
+use Sinso\Webcomponents\DataProviding\Helpers\InlineItemsHelper;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use TYPO3\CMS\Core\Context\Context;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Domain\Repository\PageRepository;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
+
+#[CoversClass(InlineItemsHelper::class)]
+final class InlineItemsHelperTest extends UnitTestCase
+{
+    private InlineItemsHelper $subject;
+
+    protected bool $resetSingletonInstances = true;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->subject = new InlineItemsHelper(
+            self::createStub(ConnectionPool::class),
+            self::createStub(Context::class),
+            self::createStub(PageRepository::class),
+        );
+    }
+
+    #[Test]
+    public function throwsExceptionIfTcaIsNotLoadable(): void
+    {
+        self::expectExceptionCode(1587038305);
+
+        $this->subject->loadInlineItems(['my_field' => 1], 'my_field', 'my_table');
+    }
+
+    #[Test]
+    public function throwsExceptionIfFieldIsNotInline(): void
+    {
+        $GLOBALS['TCA'] = ArrayUtility::setValueByPath($GLOBALS['TCA'] ?? [], 'my_table/columns/my_field/config/type', 'text');
+
+        self::expectExceptionCode(1686299043);
+
+        $this->subject->loadInlineItems(['my_field' => 1], 'my_field', 'my_table');
+
+        $GLOBALS['TCA'] = ArrayUtility::removeByPath($GLOBALS['TCA'], 'my_table/columns/my_field/config/type');
+    }
+}