In Firefox ctrl+enter prepends www. and appends .com to whatever word you’ve typed in the address bar, then loads it. So for www.ikea.com, just type ikea then press ctrl+enter.

That was just a simple example. The safari implementation is better, I type in “price” and it expands that to “Priceline.com”; just press enter to go directly there, otherwise either keep typing to narrow or down arrow and enter to search

I use Duckduckgo for search and when I enter anything in the address bar and append !, then I am automatically redirected to the first result of the search. Works perfectly in Firefox.