Hmm strange did you restart the browser?
/facepalm
Restarting the browser has restored the normal function of pop-up blocking.
I swapped from Foxit to PDF X-change no real reason. I will warn I have not gotten PDFs to work great in Opera ever but I don't look at enough PDFs to figure out why.
Downsides... getting up in front of a large number of people to talk; being able to explain things to a variety of different learners; need to continue learning yourself; continued production of research.