IceRaven is a close fork, so it will almost certainly apply to IceRaven, too (maybe with a short delay).

Loading extensions from files, I would not assume to work. Even their current developer workflow requires using an AMO collection.
Someone could reupload Bypass Paywall Clean to AMO. As I understand from quick research, the DMCA takedown request was not challenged by the dev. Or you can use another paywall removal extension.