In a contest open to Mozilla Firefox developers, participants are challenged to create extensions that use the Twilio APIs, with the goal of winning prizes such as a Netbook and $100 in developer credit. The contest has a deadline of July 25th and is open to submissions of multiple extensions, with no limit on the number of entries per winner. Participants can find resources and inspiration through Twilio's developer community hub, including API documentation, SDKs, and sample apps.