Firefox add-on technology is modernizing

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  • Creator: andrewtruong
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Add-ons are programs that add extra features to Firefox. Anyone can create an add-on and make it available to Firefox users who want to personalize their online experience.

In the past, add-ons often stopped working each time a new version of Firefox is released, because developers had to update them every six weeks to keep them compatible. To address this (and other issues), we overhauled the underlying technology for building add-ons.

Outside of rare instances, add-ons created with the new standard won’t break in new Firefox releases.

Note: Starting in Firefox 57, which will be released in November 2017, only add-ons built with this new technology will work in Firefox.

Starting in Firefox 57, which will be released in November 2017, only add-ons built with this new technology will work in Firefox. These are indicated by the “Compatible with Firefox 57+” label on addons.mozilla.org (AMO). Add-ons built with the old technology are labeled “Legacy” on the about:addons tab.

We recommend you install add-ons with the “Compatible with Firefox 57+” label to ensure compatibility with Firefox beyond November 2017.

If you are the developer of a legacy add-on, resources are available to help you migrate to the new standard.