updated advanced pack to 3.12.0:

Reports:

    Non-aggregated columns in Grid report export.
    Normalized table mode for 2-dimensional Grid reports.
    Ability to create internal reports via the UI.
    Ability to show/hide and resize columns in the list report result view.

custom/Espo/Modules/Advanced/Tools/Report/Api/PostRunGridPreview.php

@@ -11,7 +11,7 @@
  * usage to the software or any modified version or derivative work of the software
  * created by or for you.
  *
- * Copyright (C) 2015-2025 EspoCRM, Inc.
+ * Copyright (C) 2015-2026 EspoCRM, Inc.
  *
  * License ID: 19bc86a68a7bb01f458cb391d43a9212
  ************************************************************************************/
@@ -25,6 +25,7 @@ use Espo\Core\Api\Request;
 use Espo\Core\Api\Response;
 use Espo\Core\Api\ResponseComposer;
 use Espo\Core\Exceptions\BadRequest;
+use Espo\Core\Exceptions\Error\Body;
 use Espo\Core\Exceptions\Forbidden;
 use Espo\Core\Select\Where\Item as WhereItem;
 use Espo\Core\Utils\Json;
@@ -74,6 +75,7 @@ class PostRunGridPreview implements Action
 
     /**
      * @throws BadRequest
+     * @throws Forbidden
      */
     private function fetchData(Request $request): stdClass
     {
@@ -83,6 +85,15 @@ class PostRunGridPreview implements Action
             throw new BadRequest("No data.");
         }
 
+        $internalClassName = $data->internalClassName ?? null;
+        $isInternal = $data->isInternal ?? false;
+
+        if (($internalClassName !== null || $isInternal) && !$this->user->isAdmin()) {
+            throw Forbidden::createWithBody('onlyAdminCanPreviewInternalReports',
+                Body::create()->withMessageTranslation('onlyAdminCanPreviewInternalReports', Report::ENTITY_TYPE)
+            );
+        }
+
         return $data;
     }