texto en negritaThe Firefox Configuration Editor (about:config page) lists application settings known as preferences that are read from the prefs.js and user.js files in the Firefox profile and from application defaults. Many of these preferences are advanced settings that are not present in the OptionsPreferences dialog. This article describes how to use the about:config page to view, change, or reset Firefox preference settings.

Opening about:config

Escribe about:config en la Barra de direcciones y pulsa EnterReturn.
Puede aparecer una página de advertencia. Haz clic en Aceptar el riesgo y continuar para acceder a la página ""about:config.

Adding, modifying and resetting preferences

To add a new preference, right-clickcontrol-click anywhere in the list of preferences. In the context menu, select New, select the type of preference (String, Integer, or Boolean) you are adding, and then follow the prompts to enter the preference name and value.

• String is any sequence of text
• Integer is a number
• Boolean is true or false

To modify an existing preference, right-clickcontrol-click on the preference, select Modify and type in the new value. For boolean (true-false) preferences, Toggle will be the selection offered.

To reset a preference to its default value or to remove an added preference, right-clickcontrol-click on the preference and select Reset. If you added the entry using about:config, the preference will no longer be listed after restarting Firefox. (To reset all preferences, see the article Restablecer las preferencias).

Searching for preferences

You can use the Search: box at the top of the about:config page to quickly find specific preferences. For example, if you enter snippet in the Search box, it will bring up the browser.aboutHomeSnippets.updateUrl preference. Note that preference names themselves are case-sensitive but search terms are not.

Based on information from About:config (mozillaZine KB)