On this page
Working without the address bar
The address bar can be hidden entirely; double-clicking a tab is how you navigate instead.
Hiding it
Alt+Cmd+A hides or shows the address bar. Hidden, the browser is page and tabs and nothing else.
It is not gone, only out of the way — it peeks back when focused, and Escape dismisses it again.
Navigating instead
Double-click any tab and it opens into a text field over itself: type a URL, Enter goes, Escape backs out. Tabs in a stack's second row do the same.
Back and forward remain Cmd+Left and Cmd+Right, and the command palette on F2 reaches anything else.