At least people can now work on it and port it to any system that can run it.
I don't personally think that's an upside for stealing someone's property. And though you took it out of your own repo, you have a link to another repo, and I'm not sure that's what we really want to host here. There are plenty of places for any interested party to find that information. As Deo alluded to, there's no license. So it's not really legal to even work on, truthfully. The rules don't change when it's a profit making organization. And it's pretty obvious that they consider it theirs
Is the work licensed under an open source license? If so, which open source license? Are the allegedly infringing files being used under the open source license, or are they in violation of the license?
This is proprietary source code owned by Opera Software AS.