Improve HTMX request detection by using request.headers and falling back to META for compatibility

generic/views.py

@@ -1217,9 +1217,17 @@ class ExamViews(View, LoginRequiredMixin):
         }
 
         # If this is an HTMX request, return only the fragment so the client
-        # can swap it into the page. HTMX sends the HX-Request header which
+        # can swap it into the page. HTMX sets the `HX-Request` header; use
-        # is available in Django as HTTP_HX_REQUEST in request.META.
+        # request.headers (case-insensitive) where available and fall back to
-        if request.META.get("HTTP_HX_REQUEST") == "true":
+        # the META variant for older environments/proxies.
+        is_htmx = False
+        try:
+            is_htmx = request.headers.get("HX-Request", "").lower() == "true"
+        except Exception:
+            # Fall back to META if request.headers isn't available (older Django)
+            is_htmx = request.META.get("HTTP_HX_REQUEST", "") == "true"
+
+        if is_htmx:
             return render(request, "generic/partials/exam_review_question_fragment.html", context)
 
         return render(request, "generic/exam_review_question.html", context)