By default I use Google and it shows search suggestions, but when I add a custom search engine like https://www.google.com/search?q=
, or a completely different one, I don’t get any. I don’t really care where the suggestions are coming from, they could be the same as the one for the default engine.
If you want to be able to add custom engines directly from the settings, in
about:config
addbrowser.urlbar.update2.engineAliasRefresh
and set the value totrue
, after that you should see Add button inabout:preferences#search
Edit: nvm, there doesn’t seem to be field for suggestions…
Edit2: There’s also https://mycroftproject.com/, where you can try to find the search engine you want.