I can't see any good reason to force us to use something we don't want. If I type "y chromosome haplogroup" I want it to use DuckDuck Go to search for that phrase, not search Yahoo (a search engine I've never used in my 30 years on the Internet) for "chromosome haplogroup." Further, I use Wiktionary & WisdomLib more often than Wikipedia, yet am forces to use W only for Wikipedia.
I attempted the option of only using tab for specialized searches, but Tab causes Opera to cycle through the suggestions & bookmarks instead. That being the case, I don't even know why it's listed as an option.
Why is a browser with built-in privacy & ad-blocking features not allowing me to remove Google, Bing, Yahoo, or Amazon searches? I've been using the browser for two years and this still hasn't been resolved. The previous requests have been closed without any indication of attempted resolution. Now more than ever people are jumping ship from Google products. Opera should be there to catch them with open arms. Firefox is kicking your ass at welcoming former Chrome users.