Specify a regular express to match attribute values and/or text, and the CSS to apply to the elements containing the matches.
To get started, open "Preferences" through the Firefox Add-Ons Manager, copy the example JSON into the textarea, modify the example if you'd like, click "Save". The example hides links to the listed domains by setting "visiblity" to "hidden".
Don't forgot to double '\' because '\' is escape in JSON and Regular Expression.
