@LGB: Hiya, just thought I'd better mention you spelt my name wrong. I guess it was just a typo, so no worries.
Well, it's been a while since I dabbled with the mega65, but when I was, some of my learning curve regarding the inbuilt monitor was covered in this thread:
In there I tried to assemble a simple example but run into some trouble.
At the time, I think I got a hint somewhere that there was a far jump opcode (JMPF?), can't recall from where, possibly from Paul's blog or elsewhere. Since the monitor wasn't aware of it, I worked around it on that occasion with a forced beq.
As for whether that's a new opcode or not or whether I was mistaken to believe in its existence altogether, I don't know, happy to hear from you on the matter if you can confirm one way or the other.
As for whether new opcodes exist, again, can't give you specifics, just a recollection of reading the Paul's blog from start to finish, twice, and recalling reading something about him adding more to this cpu than was there initially. I seem to also recall someone asking in the comments section whether a new opcode could be added and him saying it wasn't possible due to all possible opcode values being consumed. Again, this recollection is no guarantee that I'm right on the matter, so if you or Paul want to set the record straight here, that's fine by me :-)