Firefox 47 will be released on June 7th. Here’s the list of changes that went into this version that can affect add-on compatibility. There is more information available in Firefox 47 for Developers, so you should also give it a look.
- Remove FUEL. The FUEL library has been deprecated since Firefox 40.
- Remove the about:customizing preloading hack. The UI customization panel no longer opens using the about:customizing URL.
- Move gDevTools.jsm to a commonjs module. Instead of loading the module using
Cu.import, you should now use
require("devtools/client/framework/devtools-browser");. The module still works for backward compatibility, but it will be removed in the future.
- Don’t let web pages link to view-source: URLs.
TabCloseevents should provide more detail about tabs moved between windows.
- Remove tabs’
TabLabelModifiedevent. This is a reversal from previous work on supporting a separate label for tabs.
- CookieManager should remove cookies only if they match the userContextId. This changes
nsICookieManager.removeby adding a new required argument (
originAttributes). Update: these changes may be temporarily reverted in bug 1259169, but you should still prepare for them.
- Various changes to
nsIX509CertDB: bug 1064402, bug 1241646, bug 1241650. Many functions changed here, so I won’t list them.
- Remove uses of
nsIEnumeratorfrom PSM. This changes the functions
listTokens, listModules, and
listSlots, both of which now return
History.removeVisitsByFilterand deprecate it.
- Debugging auto-close XUL panels is painful. Now you can debug popup panels in add-ons.
- Support frames similar to mozbrowser on desktop Firefox. This enables a new iframe API that makes the content believe it’s being loaded in a top-level window.
Let me know in the comments if there’s anything missing or incorrect on these lists. If your add-on breaks on Firefox 47, I’d like to know.
The automatic compatibility validation and upgrade for add-ons on AMO will happen in a few weeks, so keep an eye on your email if you have an add-on listed on our site with its compatibility set to Firefox 46.