[Request] add option to disable search fallback in open URL/history/bookmark tool

I have never been a fan of the notion of combining Web searching with a tool that is used to invoke bookmark/history or manual URL entry. It means every typo gets sent live, and clutters up the history. I can easily enough disable the search engine fallback by setting the search engine to "about:blank" in advanced settings---so for that part of the matter I'm satisfied.

What would be nice however, as an alternative, is to have that field on a checkbox that when disabled also modifies the behaviour to select and invoke the first match in the result list with return. Since return all by itself would no longer serve any purpose, being able to dodge that somewhat annoying DownArrow + Return twitch that brings your hand off the home row would be very nice. The whole thing about Vim is that you can largely ignore those awkwardly placed arrow keys, and having to rely upon them (or the mouse) for selecting search results feels to me the weakest implementation in Vimium's otherwise well executed philosophy.

P.S. If at all possible it would be nice to pull from the browser's preferences with regards to default search engine.

Start with the open URL/history/bookmark tool and its advanced-settings search engine option. Check how disabling search fallback should affect result selection and Return behavior, and whether browser search preferences are in scope. Done means the requested option works consistently and its behavior is covered by the project’s existing checks.