Firefox 45 will be
released on March 8th. Here’s the list of changes that went into this version
that can affect add-on compatibility. There is more information
available in
Firefox 45 for Developers, so you should also give it a look.
General
UI
XPCOM
Signing
- Firefox is currently enforcing add-on signing,
with a preference to override it. Firefox 46 will remove the preference
entirely , which means your add-on will need to be signed in order to
run in release versions of Firefox. You can read about your options here.
New
- Support a simplified JSON add-on update protocol. Firefox now supports a JSON update file for add-ons that manage their own automatic updates, as an alternative
to the existing XML format. For new add-ons, we suggest using the JSON
format. You shouldn’t immediately switch for older add-ons until most of
your users are on 45 and later.
http://blog.mozilla.org/addons/2016/02/05/compatibility-for-firefox-45/