Fix collection class with missing filter definition

composer.json

@@ -31,7 +31,7 @@
   "require": {
     "php": "^8.2",
     "ext-dom": "*",
-    "contao-community-alliance/dc-general": "^2.4.12",
+    "contao-community-alliance/dc-general": "^2.4.13",
     "contao-community-alliance/events-contao-bindings": "^5.0",
     "contao-community-alliance/meta-palettes": "^2.0.10",
     "contao-community-alliance/translator": "^2.5",

src/CoreBundle/Resources/contao/dca/tl_metamodel_filtersetting.php

@@ -493,7 +493,7 @@
                 'mandatory'      => true,
                 'tl_class'       => 'clr',
             ],
-            'sql'         => "text NOT NULL default ''"
+            'sql'         => 'text NULL'
         ],
         'label'                => [
             'label'       => 'label.label',

src/Filter/Setting/Collection.php

@@ -3,7 +3,7 @@
 /**
  * This file is part of MetaModels/core.
  *
- * (c) 2012-2024 The MetaModels team.
+ * (c) 2012-2026 The MetaModels team.
  *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
@@ -17,7 +17,7 @@
  * @author     Sven Baumann <baumann.sv@gmail.com>
  * @author     Richard Henkenjohann <richardhenkenjohann@googlemail.com>
  * @author     Ingolf Steinhardt <info@e-spin.de>
- * @copyright  2012-2024 The MetaModels team.
+ * @copyright  2012-2026 The MetaModels team.
  * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0-or-later
  * @filesource
  */
@@ -208,6 +208,10 @@ public function getParameterFilterWidgets(
         $arrJumpTo,
         FrontendFilterOptions $objFrontendFilterOptions
     ) {
+        if (null === $this->metaModel) {
+            return [];
+        }
+
         $parameters       = [];
         $metaModel        = $this->getMetaModel();
         $previousLanguage = ($metaModel instanceof ITranslatedMetaModel)

tests/Filter/Setting/CollectionTest.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * This file is part of MetaModels/core.
+ *
+ * (c) 2012-2026 The MetaModels team.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * This project is provided in good faith and hope to be usable by anyone.
+ *
+ * @package    MetaModels/core
+ * @author     Ingolf Steinhardt <info@e-spin.de>
+ * @copyright  2012-2026 The MetaModels team.
+ * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0-or-later
+ * @filesource
+ */
+
+namespace MetaModels\Test\Filter\Setting;
+
+use MetaModels\Filter\Setting\Collection;
+use MetaModels\FrontendIntegration\FrontendFilterOptions;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @covers \MetaModels\Filter\Setting\Collection
+ */
+#[CoversClass(Collection::class)]
+class CollectionTest extends TestCase
+{
+    /**
+     * When no MetaModel is set (e.g. FE list module with no filter configured),
+     * getParameterFilterWidgets() must return an empty array instead of throwing a RuntimeException.
+     */
+    public function testGetParameterFilterWidgetsReturnsEmptyArrayWhenNoMetaModelSet(): void
+    {
+        $collection = new Collection([]);
+
+        $result = $collection->getParameterFilterWidgets([], [], new FrontendFilterOptions());
+
+        self::assertSame([], $result);
+    }
+
+    /**
+     * getParameters() returns an empty array when the collection has no settings.
+     */
+    public function testGetParametersReturnsEmptyArrayWhenNoSettings(): void
+    {
+        $collection = new Collection([]);
+
+        self::assertSame([], $collection->getParameters());
+    }
+}