In an interview before the presentation, Snyder said that Firefox enjoys a community of users in the millions worldwide. Of these, there are about 10,000 users who regularly download what are called nightly builds. Whenever the Mozilla security team puts out new fixes in the nightly builds, it's these 10,000 users who test the fixes on a wide variety of machines and under a wide variety of circumstances. Thus, Mozilla is able to roll out its security patches faster and with fewer headaches.
Because Mozilla enjoys a very enthusiastic community of users, the company decided to put out tools in the hands of its users that'll help make future releases of Firefox even stronger. After thinking about it, it decided the tools could be used on all browsers, not just its own because many similar vulnerabilities affect other browsers as well. The tool can be downloaded from Mozilla.