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Getting Started

You must have a checkout of Firefox that you can build and run. For more details see the simple build instructions, or the more detailed instructions.

You will also need an installation of NodeJS, and Git. GCLI can run under Node, and it also uses Node to build its output for Firefox.

Getting GCLI

GCLI is stored in git. There are two repositories of note. Most of the up-to-date development happens in joewalker's repo; when changes have landed in mozilla-central, then they also appear in the mozilla fork.

The GCLI build step alters your checkout of mozilla-central, so it needs the FIREFOX_HOME environment variable to point at the right directory.

$ export FIREFOX_HOME=`pwd`

Getting and running GCLI looks like this:

$ git clone git://
$ cd gcli
$ node gcli.js
Serving GCLI to http://localhost:9999/
This is also a limited GCLI prompt. Type 'help' for a list of commands, CTRL+C twice to exit:

The easiest way to build GCLI into an installation of firefox is like this:

$ node gcli.js firefox

This assumes that you have setup the $FIREFOX_HOME environment variable as specified earlier. Alternatively you can do this:

$ node gcli.js firefox /path/to/mozilla-central

Now you can make changes to the GCLI source, test it in a web browser, and export a gcli.jsm package to run in Firefox.

Document Tags and Contributors

 Contributors to this page: Pejman-Platform, kscarfone, Quentin, jwalker
 Last updated by: Pejman-Platform,