I don't think catbox.moe has the bandwidth lately.
It works, but it plays slowly (It took 90 seconds to download all 17.5 MB directly, which is longer than the gif lasts).
I've been playing around with animated WEBP files. These are much more efficient than gifs (the linked WEBP is about 330KB), but am having a hard time making them work for Lemmy.
Option 1: upload them directly to Lemmy, they get auto-recompressed and then often look like garbage
Option 2: direct-link to external host, Lemmy copies it in and auto-recompresses it with the same effect
Option 3: URL-link to an external host, which then people are reluctant to click
Option 4: Include as an inline link in the body of a post, then it looks like a text post, and support for it is variable among web clients and mobile apps