Use 9gif to extract gif url from 9gag post.
After some 9gag updates, all animation posts were converted and shown in Chrome as MP4 videos.
With 9gif extension, you still can retrieve URL to GIF for any animated post:
1. Play animation on 9gag
2. Right-click on it and choose "Get gif url for this post"
3. Clickable URL will show up at the top of the page