{"id":7158,"date":"2014-06-05T09:00:21","date_gmt":"2014-06-05T16:00:21","guid":{"rendered":"http:\/\/blog.mozilla.org\/addons\/?p=7158"},"modified":"2020-02-11T15:51:25","modified_gmt":"2020-02-11T23:51:25","slug":"how-to-develop-firefox-extension","status":"publish","type":"post","link":"https:\/\/blog.mozilla.org\/addons\/2014\/06\/05\/how-to-develop-firefox-extension\/","title":{"rendered":"How to develop a Firefox extension"},"content":{"rendered":"

Update: <\/span>Firefox has used the WebExtensions API as its extension API since 2017. We encourage you to visit Extension Workshop<\/a> to learn more about browser extensions and how you can build an extension for Firefox. You can find reference documentation for the WebExtensions API on MDN<\/a>. <\/strong><\/p>\n

Please do not reference this article for extension development, as it is out-of-date. If you are the developer of a legacy add-on, please refer to this page<\/a> for resources to help you migrate to the current API.<\/strong><\/p>\n

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It’s been a while since we published a guide on extension development in this blog, and we recently discovered that many of you are hitting a very old blog post about it. There’s plenty of documentation out there, but it can be hard to find, so here’s an overview of what you need to know about extension development.<\/p>\n

As with everything Mozilla, the first place you should look for developer documentation is the Mozilla Developer Network. There’s an add-ons section<\/strong><\/a> there where you will find everything you need to know about how to develop Firefox extensions, as well as other add-on types.<\/p>\n

There are a couple different ways to go about creating an extension for Firefox, so I covered each in the sections below.<\/p>\n

Add-ons SDK extensions<\/h3>\n

The Add-ons SDK<\/a><\/strong> is a set of simple APIs you can use to quickly build good Firefox extensions. It’s what we recommend for new developers. It should be easy to work with, especially if you’re familiar with Google Chrome extensions or userscripts. It abstracts away most of the XUL \/ XPCOM infractrusture in Firefox, giving you a more familiar HTML and JS environment to work with.<\/p>\n

The current approach to building an SDK extension is to download and set up the SDK, code locally,\u00a0 then package your extension (an XPI file) using the cfx tool included with the SDK. The SDK team is working on making this process much easier by integrating it into Firefox developer tools. Soon you’ll be able to build your extensions very quickly, right from Firefox.<\/p>\n

You can learn more about the SDK and get help here:<\/p>\n