Google Chrome was the first browser to use a singular bar, combining the search and address bars together. When it launched, this was one of its main features.Opera, Opera Neon, Microsoft Edge also uses a uni-bar approach at the top of the browser for both URL input and search queries.
In Firefox , the Search box is not present by default on the toolbar. The address bar is intended to replace it. If you find this change inconvenient, you might want to add the search box back to the address bar.
Click on the hamburger menu button
Options > Search > Search Bar ” and choosing the second option, “Add Search bar in toolbar”
That’s it. The search box will appear next to the address bar