I has been using Firefox since.... well, I can't remember! But I remember using "Phoenix" ;)
I'm also a power user of the Hackbar extension for long time and then become a contributor to the code. As web application tester I know which features Hackbar is lacking of and in my spare time I try to help the community (and myself) to have a better tool for web testing.
I'm focused on writing extension to help web application testers to improve their daily work, making Firefox their main tool and not just a browser.