diff --git a/composer.json b/composer.json
index 1cd9798..0a79ac0 100644
--- a/composer.json
+++ b/composer.json
@@ -6,5 +6,8 @@
   "support": {
     "issues": "https://www.drupal.org/project/issues/views_accordion"
   },
+  "require": {
+    "drupal/core": "^8 || ^9"
+  },
   "license": "GPL-2.0+"
 }
diff --git a/tests/src/Functional/ViewsAccordionTest.php b/tests/src/Functional/ViewsAccordionTest.php
index 626f0b3..01a8bc5 100644
--- a/tests/src/Functional/ViewsAccordionTest.php
+++ b/tests/src/Functional/ViewsAccordionTest.php
@@ -11,6 +11,12 @@ use Drupal\Tests\BrowserTestBase;
  */
 class ViewsAccordionTest extends BrowserTestBase {
 
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
   /**
    * {@inheritdoc}
    */
diff --git a/tests/src/FunctionalJavascript/ViewsAccordionTest.php b/tests/src/FunctionalJavascript/ViewsAccordionTest.php
index 2662544..c6e028e 100644
--- a/tests/src/FunctionalJavascript/ViewsAccordionTest.php
+++ b/tests/src/FunctionalJavascript/ViewsAccordionTest.php
@@ -13,6 +13,11 @@ use Drupal\Tests\node\Traits\NodeCreationTrait;
 class ViewsAccordionTest extends WebDriverTestBase {
   use NodeCreationTrait;
 
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'stark';
+
   /**
    * {@inheritdoc}
    */
diff --git a/views_accordion.info.yml b/views_accordion.info.yml
index 6fe4535..f287d04 100755
--- a/views_accordion.info.yml
+++ b/views_accordion.info.yml
@@ -2,5 +2,6 @@ name: Views Accordion
 type: module
 description: 'Provides an accordion views display plugin.'
 core: 8.x
+core_version_requirement: ^8 || ^9
 dependencies:
   - drupal:views