@leocg I think I tried that but got some sort of error. I'll give it another shot. Thanks!

So simply copying the folder there doesn't register it. Any idea how to do this? It's no longer offered in the extension store.

Thanks!

So Opera wouldn't work after migrating data from my old Mac Studio to the new one. I reinstalled and everything, for the most part is fine, all the bookmarks, etc.

However, a couple of extensions which are no longer in the store weren't brought over. I still have the old Mac and I'd like to move them over manually.

The answers I've gotten on the Web don't seem accurate. Where would I find those extensions on the old Mac?