diff --git a/advanced_search.info.yml b/advanced_search.info.yml
index 5420ad9..c6189d6 100644
--- a/advanced_search.info.yml
+++ b/advanced_search.info.yml
@@ -4,7 +4,7 @@ name: 'Advanced Search'
 description: "Creates an Advanced Search block and other enhancements to search."
 type: module
 package: Islandora
-core_version_requirement: ^8 || ^9
+core_version_requirement: ^9.3
 dependencies:
   - drupal:facets
   - drupal:facets_summary
diff --git a/src/Controller/AjaxBlocksController.php b/src/Controller/AjaxBlocksController.php
index 9eb7739..c5e3fb8 100644
--- a/src/Controller/AjaxBlocksController.php
+++ b/src/Controller/AjaxBlocksController.php
@@ -11,7 +11,6 @@ use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Routing\CurrentRouteMatch;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\Routing\RouterInterface;
 
@@ -136,7 +135,7 @@ class AjaxBlocksController extends ControllerBase {
     }
 
     $new_request = Request::create($path);
-    $request_stack = new RequestStack();
+    $request_stack = \Drupal::requestStack();
     $processed = $this->pathProcessor->processInbound($new_request->getPathInfo(), $new_request);
 
     $this->currentPath->setPath($processed);
diff --git a/src/Form/AdvancedSearchForm.php b/src/Form/AdvancedSearchForm.php
index 7637cf4..4316eed 100644
--- a/src/Form/AdvancedSearchForm.php
+++ b/src/Form/AdvancedSearchForm.php
@@ -71,7 +71,7 @@ class AdvancedSearchForm extends FormBase {
    */
   public static function create(ContainerInterface $container) {
     return new static(
-      $container->get('request_stack')->getMasterRequest(),
+      $container->get('request_stack')->getMainRequest(),
       $container->get('current_route_match')
     );
   }
diff --git a/src/Plugin/Block/AdvancedSearchBlock.php b/src/Plugin/Block/AdvancedSearchBlock.php
index 7ce64fe..5db6c2e 100644
--- a/src/Plugin/Block/AdvancedSearchBlock.php
+++ b/src/Plugin/Block/AdvancedSearchBlock.php
@@ -108,7 +108,7 @@ class AdvancedSearchBlock extends BlockBase implements ContainerFactoryPluginInt
       $plugin_definition,
       $container->get('plugin.manager.search_api.display'),
       $container->get('form_builder'),
-      $container->get('request_stack')->getMasterRequest()
+      $container->get('request_stack')->getMainRequest()
     );
   }
 
diff --git a/src/Plugin/Block/SearchResultsPagerBlock.php b/src/Plugin/Block/SearchResultsPagerBlock.php
index 498cc64..b47edb8 100644
--- a/src/Plugin/Block/SearchResultsPagerBlock.php
+++ b/src/Plugin/Block/SearchResultsPagerBlock.php
@@ -58,7 +58,7 @@ class SearchResultsPagerBlock extends BlockBase implements ContainerFactoryPlugi
       $configuration,
       $plugin_id,
       $plugin_definition,
-      $container->get('request_stack')->getMasterRequest()
+      $container->get('request_stack')->getMainRequest()
     );
   }