Hello, thanks for writing in about this, and sorry for the delay in getting back to you. I checked and verified that animated gifs are not a supported format for posts. 

However, this sounds like a good idea to share to our Ideas Board so that others can also vote on your idea. We kindly ask that you review our Idea Guidelines, particularly the “What makes a good idea” section, to ensure that your ideas are clear, concise, and can reach as many others as possible.

Thank you for your contribution, we value your input.

That sounds frustrating! Animated GIFs can sometimes face compatibility issues depending on the platform. If it works in the post creation but not in the feed, it might be worth reporting as a bug. For more about animated content, check out toonkor. Hope you find a solution soon!