Enhance your usage of Firefox

When installing Ubuntu on one of the new machines we get from time to time, there's a common mechanism I repeat over and over with Firefox:
  1. install the Firebug extension
  2. install the Web Developer extension
  3. install the ShowIP extension
  4. install the GooglePreview extension
  5. change the link of the start bar icon to start Firefox, to "firefox -no-remote -ProfileManager %u" instead of "firefox %u"
The latest option allows you to launch Firefox using different profiles, each of them having its own extensions. This allows you to have a slower but fully equipped Firefox on one side and a faster but bare Firefox on the other side. If you installed all the extensions I have mentioned  (and maybe more), you might want to get another one for faster or cleaner demos. There you go, your second profile can be called "demos". Oh, and you might want to change the look of your Firefox a little bit with the Persona extension. That's quickly boring as well, and it doesn't help usability much, but still, considering your browser is the tool you probably use most as a web developer...