It will be another change I will hardly notice as I don't use the default search in any case.
I have been using the "Add to Search Bar" extension for a long time. I have 10 different searches on it currently and although one is Yahoo I seldom use it.
Also 4 different Google searches including the image search that loads the old style search.
I haven't checked on my regular FF install but I notice on PaleMoon the extension is still at 2.0 although it is currently at 2.7. Works fine so I'm leaving it that way.
"... With Add to Search Bar you can add the search functionality of any page to the search box with no effort. ..."
Add to Search Bar - Search on Fire