Not all Firefox users like the change.

Je confirme, je préfère la simplicité et ne pas cacher ma barre de favoris :D

Firefox users may roll back the address bar changes currently but some of the preferences will be removed in the near future (likely in Firefox 77).

For now though, Firefox users may make the following configuration changes to get the old address bar back:

    Load about:config in the browser's address bar.
    Confirm that you will be careful.
    Search for the following preferences and set them all to FALSE
        browser.urlbar.openViewOnFocus
        browser.urlbar.update1
        browser.urlbar.update1.interventions
        browser.urlbar.update1.searchTips
        browser.urlbar.update1.view.stripHttps
    Restart the Firefox web browser.