Just a quick tip that if you are a developer and you lately upgraded Firefox4 to Firefox5 (or why not give Aurora a try?) it tells you that Firebug is not compatible and can’t find an upgrade.
However, there is a compatible version of Firebug (v1.8) available for you: get it here.
Now you can get the latest Firefox goodness and still debug your code.
About Chris Heilmann
Principal Evangelist at Mozilla for HTML5 and open web. Let's fix this!