This is just a refresher for myself. I’ve started using Firefox Beta 4.0b1 without the menu bar and navigation bar for a very minimalist view.
Using it this way makes keyboard shortcuts that much more important for efficient browsing.
Go to your default search engine = ctrl & k
Go to a URL = ctrl & l
Open the downloads sidebar = ctrl & j
Go to your home page = alt & home
Find in the current page = ctrl & f
To set your default search engine to something else: hit ctrl & l, type about:config.
search for browser.search.defaultenginename and change it to whatever you want, in my case Bing.