Fix #19750 : Handle reference images correctly in image edit

- Modified get_last_images() to distinguish between user-uploaded and assistant-generated images
- Fixes bug where uploading a reference image after generation would ignore the previously generated image
- Assistant images are now prioritized for editing with user references appended

backend/open_webui/utils/middleware.py

@@ -716,20 +716,37 @@ async def chat_web_search_handler(
     return form_data
 
 
-def get_last_images(message_list):
+
+
+def get_last_user_images(message_list):
+    """Get all images from the last USER message only"""
     images = []
     for message in reversed(message_list):
-        images_flag = False
+        if message.get("role") == "user":
             for file in message.get("files", []):
                 if file.get("type") == "image":
                     images.append(file.get("url"))
-                images_flag = True
+            break  # Only from most recent user message
-
-        if images_flag:
-            break
-
     return images
 
+def get_last_assistant_image(message_list):
+    """Get the most recent ASSISTANT-generated image"""
+    for message in reversed(message_list):
+        if message.get("role") == "assistant":
+            for file in message.get("files", []):
+                if file.get("type") == "image":
+                    return file.get("url")
+    return None
+
+def get_last_images(message_list):
+    assistant_image = get_last_assistant_image(message_list)
+    user_images = get_last_user_images(message_list)
+
+    if assistant_image:
+        return [assistant_image] + user_images 
+
+    return user_images
+
 
 def get_image_urls(delta_images, request, metadata, user) -> list[str]:
     if not isinstance(delta_images, list):