I just found myself looking up the difference between dialog and dialogue when I found myself uncomfortable typing dialog, to mean words exchange between characters in a story, and changed it to dialogue. I am pretty sure I have been leaving off the -ue in that usage recently, without being tripped over into rebelling.
Looks like it’s overwhelmingly dialogue until very modern times, mainly as a computer term for a dialog box. This makes sense. Conversely, catalog was adopted more universally over catalogue, as an American spelling, long ago.