Merge pull request '尝试解决 Discord 无法读取图片的问题' (#30) from bugfix/discord-image-download into master

Reviewed-on: #30

konabot/common/nb/extract_image.py

@@ -127,7 +127,7 @@ async def extract_image_from_message(
         for a in evt.attachments:
             if "image/" not in a.content_type:
                 continue
-            url = a.proxy_url
+            url = a.url
             return (await download_image_bytes(url)).bind(bytes_to_pil)
 
     for seg in UniMessage.of(msg, bot):