добавил вызов gtag через window.onload

apps/course/templates/course/course.html

@@ -395,7 +395,7 @@
 {% block foot %}
 {% include "templates/blocks/popup_course_buy.html" %}
 <script type="text/javascript" src="{% static 'course.js' %}"></script>
-<script defer>
+<script>
 
   console.log('{{ course.id }}');
   console.log('{{ course.title }}');
@@ -403,17 +403,19 @@
   console.log('{{ course.category.title }}');
   console.log('{{ course.price }}');
 
-  gtag('event', 'view_item', {
-  "items": [
-    {
-      "id": "{{ course.id }}",
-      "name": "{{ course.title }}",
-      "list_name": "Search Results",
-      "brand": "Lil.School {{ course.author.get_full_name }}",
-      "category": "{{ course.category.title }}",
-      "price": "{{ course.price }}"
-    }
-  ]
-});
+  window.onload = function () {
+    gtag('event', 'view_item', {
+    "items": [
+      {
+        "id": "{{ course.id }}",
+        "name": "{{ course.title }}",
+        "list_name": "Search Results",
+        "brand": "Lil.School {{ course.author.get_full_name }}",
+        "category": "{{ course.category.title }}",
+        "price": "{{ course.price }}"
+      }
+    ]
+  })
+  };
 </script>
 {% endblock foot %}