ctrl-shift-N is a bad choice for a common action. I can never remember it. It's a 3 key shortcut and the letter N doesn't exist in "Go to Page". Maybe I try to remember it's for 'N'ew page. Many apps I use it's ctrl-G or Alt-G. That makes a lot more sense.
Anyway, is there a way to change the keyboard shortcut assignment? If not, that's another annoying thing about this 27 year old app. Seriously.