If China has your data they’re one step closer to having access to taking your money. Are you okay with them taking your money too? What recourse would you have?
It depends on _how_ they took your money, but there are several insurance options available for Identify Theft which includes unauthorized bank withdraws.
Given the browser is produced by Opera Software AS, all data should be held under Norwegian law (which will in the near future include the GDPR), and your recourses are through the Norwegian courts, which makes it a very different situation to something developed directly in China.
I remember reading a comment from a dev working for a mobile app shop which had been bought by a Chinese company: they got instructions to add an analytics binary blob to their app and did it.
That's an anecdote, but the point is that one can't rely on Norwegian courts for enforcing privacy.
Right, you can't stop them from pulling something like that, but you do have recourse through the Norwegian courts (whom are likely to look down on that much more so than any Chinese court!), and when Opera Limited's revenue is predominantly through it's Opera Software AS subsidiary, a large GDPR fine in Norway would be a big deal to the company.