Mozilla also does a great job at marketing your extensions too. I've built two Firefox extensions and they're both steadily growing in usage everyday because of

Mozilla also does a great job at marketing your extensions too. I've built two Firefox extensions and they're both steadily growing in usage everyday because of the traffic that's sourced on the Mozilla site and also because it's frequently displayed in users' add-on manager. In contrast, my Chrome extension has been pretty static in usage - for me to see any hikes I'm actually going to have to hustle and market it. Firefox lets me kick back, be lazy, and helps me with branding it.