That's because Firefox for iOS is really just a skin around Safari's WebKit-based engine, because Apple plays the evil gatekeeper on their app store and doesn't allow Firefox to use their own rendering engine. (Chrome on iOS is also effectively just a Safari wrapper.)
It's one of the many reasons I think iOS is a horrible choice for a privacy-conscious user.
It's one of the many reasons I think iOS is a horrible choice for a privacy-conscious user.
Firefox for Android supports extensions.