The Add-on SDK is a software development kit that provides a set of tools and APIs for building, testing, and packaging Firefox add-ons.
Obtain the SDK in your favorite compression format:
Then unpack the archive, open the addon-sdk-XX/README.txt file, and follow its instructions.
Major Changes Since XX
See the complete list of known issues and requests for enhancement. We've listed some of the issues you're most likely to encounter separately below.