===Is WebExtensions a stable API?===
Yes. Each API will be documented on MDN in regards to its standards and/or experimental status. API APIs that are [[WebExtensions/DeprecationPolicy|deprecated will also be noted]]. More details on how to understand the status of the WebExtensions API can be found on the [https://wiki.mozilla.org/WebExtensions/Spec wiki page].
===Are there WebExtension API outside of the draft specification?===