It is official, @Vivaldi have included advertisment into your address-bar suggestions. This is opt-out, so it is enabled by default and is triggered only after two characters in your address-bar.
For me, the address-bar in a browser is like terminal in Linux, what I type is sensitive and should not be cluttered with advert and junk. #Vivaldi crossed a big red line here. Having advert in favorites and quickdial is one thing, having advert in address-bar is another.