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Distribution, Firefox Extensions

This tutorial is a legacy tutorial that is no longer maintained, nor supported by Rietta Inc. It was written by nine students at Georgia Tech in 2005, for Firefox 1.5, which is highly out of date. This page is preserved for historical purposes.

Your Guide to Writing Firefox Extensions

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Congratulations! If you are to this step you must have something working! In order for you to share your extensions with others you will first need to package the extension. After all you have gone through, this will be quite easy! Packaging

Simply follow these two steps to package your extension:

  1. Open up your MyExt folder and create a zip file containing all of the files and folders. Note that you should not zip up the MyExt folder itself, instead zip of the files and folders that are inside it.
  2. Rename the file extension from .zip to .xpi.

The name of your .xpi file does not matter; just pick something that makes sense to you. To test your package you can simply drag the .xpi file into your Firefox browser. Once you let go of the file, Firefox should recognize it as an extension and ask you if you would like to install it. Say yes!

Your Firefox extension will be unverified and thus will make you wait a few seconds before you can install it. This is to ensure you understand there could be bad code within the file. Verifying your extension requires a lot of work that is beyond this tutorial (it is quite expensive, too).

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The best way to distribute your new Firefox extension is through Mozilla’s developer website. The “Developer Control Panel” allows you to add/remove new versions of your extension, add/remove screenshots, update the compatibility information, and more. Most importantly, users will be able to download and install your extension through the built-in extension retrieval system. The URL is http://addons.mozilla.org/developers/.

You will need to register with Mozilla to be able to use this service. Click “Join Mozilla Update!” in the bottom right hand corner to register. You will need to check your email to complete the registration process (the email was sent immediately for us). Once you are logged in you will have the opportunity to upload your new extension. Please note that it will take several days for your extension to be approved by Mozilla, this limits how much ‘junk’ can be posted to the website.

Once accepted your new Firefox extension will be available along with other developers’ extensions at https://addons.mozilla.org/extensions/?application=firefox. You can also find this website through Firefox by clicking Tools, then Extensions, and then clicking the “Get More Extensions” link.

If you choose to host your Firefox extension on your own website, make sure that you serve it as application/x-xpinstall (this will be the default on most servers). This will allow people using Firefox to automatically install your new extension just by clicking the link!

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Further Reading

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