I post these updates every 3 weeks to inform add-on developers about the status of the review queues, add-on compatibility, and other happenings in the add-ons world.

The Review Queues

• Most nominations for full review are taking less than 10 weeks to review.
• 142 nominations in the queue awaiting review.
• Most updates are being reviewed within 7 weeks.
• 70 updates in the queue awaiting review.
• Most preliminary reviews are being reviewed within 7 weeks.
• 141 preliminary review submissions in the queue awaiting review.

Review times for most add-ons have improved recently  due to more volunteer activity. Add-ons that are admin-flagged or very complex are still moving along slowly, but we’re in the process of getting more paid reviewer time in the coming weeks, which should help in that area.

If you’re an add-on developer and would like to see add-ons reviewed faster, please consider joining us. Add-on reviewers get invited to Mozilla events and earn cool gear with their work. Visit our wiki page for more information.

Firefox 42 Compatibility

The compatibility blog post is up, and the automatic validation was run last week.

Firefox 43 Compatibility

This compatibility blog post should come up soon.

As always, we recommend that you test your add-ons on Beta and Firefox Developer Edition to make sure that they continue to work correctly. End users can install the Add-on Compatibility Reporter to identify and report any add-ons that aren’t working anymore.

Changes in let and const in Firefox 44

Firefox 44 includes some breaking changes that you should all be aware of. Please read the post carefully and test your add-ons on Nightly or the newest Developer Edition.

Extension Signing

The wiki page on Extension Signing has information about the timeline, as well as responses to some frequently asked questions. The current plan is to turn on enforcement by default in Firefox 43.

Electrolysis

Electrolysis, also known as e10s, is the next major compatibility change coming to Firefox. In a nutshell, Firefox will run on multiple processes now, running content code in a different process than browser code. If you have questions about this, please join the #e10s channel on IRC.

Web Extensions

If you read the post on the future of add-on development, you should know there are big changes coming. We’re investing heavily on the new WebExtensions API, so we strongly recommend that you start looking into it for your add-ons. You can track progress of its development in http://www.arewewebextensionsyet.com/.

https://blog.mozilla.org/addons/2015/11/04/add-ons-update-73/