The location bar, the place where you type in the web domain, where you want to go that also has the refresh and go back or forward buttons is gone. I don't know how, I'm thinking some sort of virus? Please help this sucks a big one. This started late last night.
in the menubar go to "View", select "Toolbars" in the dropdown menu and from within the next dropdown menu select "Customise". A panel showing a selection of icons for different functions will open. Drag the icon labelled "Location" out of this panel and drop it on where the location bar used to live at the top of the firefox window. Click "Done".
Dunno why this happened to my Firefox—perhaps Mozilla are tampering with the settings on obsolete installed versions of Firsfox now, rather than supporting them?