Left click on the toolbar and keep the button pressed. Drag the mouse downwards. You may well find that the address bar reappears. You may now have some tidying up to do to get everything in its place.
What I have found out it is is that the menus - file, edit, view, favourites, tools and help - are not on their own line above the back button as normal. They are on the same line and have "pushed" everything to the right. What I need to do is get these options back to the top on their own line.