Yup, I wouldn't expect these DL extensions to keep working. IDK what Opera's policy is, but Firefox is very strict now in banning such add-ons, and as for Chrome, forget it.
The best solutions I know of is to use a compatible Firefox fork, or a standalone program. I think standalone programs work best now, but they are getting busted too. Lucky for me, the one I use is not on a ban list yet.. TIP: Check out TorrentFreak for the latest news about this, and check the comments, you just might get lucky too.
Beyond that, don't ask me, I'm just watching the paint dry.