Steps to reproduce:

• Click into urlbar
• Enter some search term like "test"
• Select one of the search engines in the bottom bar like Bing
• [Bing] is append before the search term
• Have to press enter to search / or click on the arrow symbol

What to fix:
Searching now takes one more click or button press. Maybe it should automatically start searching when there is already text in the URL bar?

I asked Verdi about this and he said:

That’s by design. Wontfix? I think this is where we break some people’s workflows. I don’t see how we enable both behaviors without scrapping the idea. If we do what is suggested in the bug we just end up with a confusing interaction. Sometimes when you click the button it searches and sometimes it does not.

One thing we could do is to add any extension APIs necessary so that at least extensions could implement one-click searches. They might already be able to do that today, I'm not sure off hand.

(In reply to Drew Willcoxon :adw from comment #1)

I asked Verdi about this and he said:

That’s by design.

Here's an explanation of the rationale for that design. https://docs.google.com/document/d/1AGSaYXLy18PFaY5-cDH_w4VVivpqNPPuWUA7YdtbLOo/edit?usp=sharing

I don't understand why this bug is closed without a solution...

Can you improve the new design to also permit to quickly do in 2 steps (write and click) a search in the current tab but in another search engine ?

See https://bugzilla.mozilla.org/show_bug.cgi?id=1662169#c5

It is not possible by default to allow both interactions, we must pick a direction. Though we're looking into what's possible to provide as an alternative path.