Anybody care to chip in on the best way to do FF add-ons?

I wrote a Chrome extension that I use daily. Unfortunately, Chrome has become so bloated that I now have to wait a second or two (on OS X Mavericks) for the simplest things to happen. I really hate this, so I'm going to try porting it to FF, which appears to have no such problem.

It's a little surprising that the performance sweepstakes now favor FF (and Safari, which is even better), but I'm not the only person I know who's experiencing this.