There is Orion+ that can be paid for that keeps development going.
But, sure, I could imagine paying for a browser again - although I don't immediately see what features would be worth paying for.
For opera it was the custom, fast rendering engine and the email client.
Now with basically two equivalent rendering engines, I don't imagine performance in that area will be enough to pay for.
Maybe a smalltalk like developer mode with better debugger and repl support?
There is Orion+ that can be paid for that keeps development going.