Greasy Fork is available in English.
Formats embedded tweets. RES cannot do this for technical and security reasons.
Nevermind, it works now.
Well, mostly. It sometimes works, it sometimes doesn't; when it does it shows the Twitter expandos just like in Chrome, but other times it gets stuck and shows nothing.
It mostly fails when surfing a subreddit, and has only worked once so far (when reading a post's comments, where the original post was a Twitter link).
Outdated
It doesn't work anymore on its current version. Furthermore, it actually makes it so that Twitter expandos don't show even in plain text form.