@asDGreat can certainly use apps like ueli for systemwide keystroke launcher like vivaldi offers with quick command search.
Nonetheless, Operas instant search is the superior one because it stays within the same window when accessing websearch. That's the key element that makes it superior.
Don't get me wrong, Vivaldi is a terrific browser with a lot of customization and that's truly great. But its missing this exact feature what Opera has/had and no other: instant search.
I am staying inifinitely on v67 and blocking auto-updates so i can continue using this feature.