Fangs FAQ

This document provides answers to the most commonly asked questions about Fangs, the screen reader emulator plugin for Mozilla Firefox.

I just installed Fangs in Firefox 2 but the output is blank?

There is a bug in the installation script that results in some preferences not being set. To set them manually open the Firefox preferences page by typing about:config (return) in the browser address field. Create the following preferences:

  • extensions.fangs.output.defaultlang, with the value “en” (remove quotes).
  •, with the value “default” (remove quotes).

Restart the browser and Fangs should now work properly.

How do I install Fangs?

For installation instructions, please see my original blog post about Fangs.

How do I use Fangs?

After installing (and restarting Firefox) there will be a new option in the context menu. Browse to a web page, right click and select “View Fangs”. A new window will open with the text rendered by Fangs. View screenshot of Fangs in action.

My hidden elements/markup/aural css styles are not rendered by Fangs

A lot of “accessibility” features of web standards are not implemented in most screen readers. For example, JAWS makes no use of aural css features whatsoever. It also skips everything that has a CSS style of display:none. So will Fangs. Your hidden elements will stay hidden for everyone apart from source-reading propellerheads.

Why haven’t you integrated Fangs with a voice synthesizer?

The whole idea with Fangs is to provide you with a textual representation of the same ouput so that you don’t have to listen to it. Spoken text is linear by nature and takes time to parse. If you want to listen to real screen reader output you should use a modern screen reader. Fangs does not replace testing with the real thing.

I have recieved requests to make fangs an accessibility tool for Firefox. When the renderer is stable, work in that direction can begin. This will probably be a different plugin.

When will localized versions of Fangs be available?

As soon as the renderer has stabilized localization can begin. Localization needs to be done in two areas; the Fangs user interface and the Fangs renderer output. So far I have received requests and proposals for French and Spanish.

How can I keep myself up to date with new releases of Fangs?

Subscribe to the Fangs release mailing list. Instructions and subscription details can be found at the SourceForge mailing list page.

I am using the Tab Browser Extension and get weird behaviour with Fangs

The tab browser extension (TBE) forces the Fangs window into a tab. The Fangs window is an XUL window which the TBE does not seem to handle very well. Disable the TBE before using Fangs.

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