I don’t have the File function and under settings you can add Duck Duck Go as a search engine but you can only make one of a select few (Google, Bing, Yahoo, Amazon, and Wikipedia) the default search.
I’m done with it. No more. Opera is gone. Gonna try and use Safari, see how far it gets me. Hopefully Eich brings us a brand new browser soon and we can get rid of Firefox altogether.
Should be a grey arrow drop-down next to Google logo in search box at top right. Also at bottom, a small wrench w/ Manage Search Engines, to let you add engines. Only ONE can be used at a time, but you can go in and re-select a different engine at any time, or set one as default.
OR, right-click on box, go to “customize > appearance > buttons > search” and set-up your search engine buttons.