Classic Style for Favicons is a very neat extension for the browser. This add-on for Firefox puts the favicon in the URL Bar and restores the old favicon behavior with secure sites identity background colors. Optionally doesn’t show the Tab Bar when only one tab is open.
If you are feeling a ‘bit nostalgic for the way Firefox used to work, I would definitely say to give this Firefox Add-on a shot. You can pick up Classic Style for Favicons from the Firefox Add-ons website.