Note: B2G OS add-ons are based on the WebExtensions API, which is also supported in Firefox desktop starting with version 42 and is based on the extension APIs used in Chrome and Opera.
You should follow the below steps to get set up to start developing extensions.
In the Settings app on the device, select Developer > Debugging via USB > ADB and Devtools. You should now be able to debug installed apps using WebIDE, either via a USB cable, and over Wifi (no USB cable required.)
- Tutorial: https://developer.mozilla.org/en-US/docs/Mozilla/Firefox_OS/Add-ons/Developing_Firefox_OS_add-ons
- In-depth example: https://hacks.mozilla.org/2015/11/building-an-ios-style-unread-notifications-add-on-for-firefox-os/
- API reference: https://developer.mozilla.org/en-US/Add-ons/WebExtensions
- Mailing list: https://mail.mozilla.org/listinfo/dev-fxos
- Discourse forum: https://discourse.mozilla-community.org/c/add-ons/development
- IRC: irc.mozilla.org, #webextensions and #fxos
- Let us know what new APIs we should prioritize: https://webextensions.uservoice.com/forums/315663-webextension-api-ideas
- Follow us on Twitter: @MozWebExt