Opened it again and the right click menu worked.
Computers are deterministic machines, things don't randomly fix themselves. Closing a program and reopening it is the equivalent of smashing your head against the wall and expecting something other than brain damage. I'm glad it worked for you, but the fact is, something else
happened between those attempts. Either you were originally testing the popups incorrectly, or you made another change to your environment or mIRC. Just because you're "sure" nothing else happened, doesn't mean you didn't miss some other important detail. The point is that without this information, we can't help you further by telling you what happened.
In other words, I am trying
to help you, but you need to provide more information if you want an answer to your last question:
so why would any of it have changed by simply upgrading the program?
Please don't get mad at me for asking you to provide information; this is the only way we can diagnose your problem. If you want to swear by the fact that absolutely nothing else occurred except for the exact details you listed above, then the answer to your question has to be: