(For a comparison view of table and actual about:config settings, use the Fox Splitter (formerly Split Browser) extension or the new version of Fox-Splitter to show one above the other. Also check Mail and news settings for a listing of Thunderbird and Mozilla Suite/SeaMonkey mail and news preferences.

If you don't find an entry below for a given preference, check the Category:Preferences (multiple-page) listing, which includes many new preferences that have not been added here, as well as those preferences that have been migrated from sections of this article.

This article does not contain a complete list of all preferences. Users not already familiar with about:config entries should read the companion article, about:config, which describes how to modify values and work with the about:config list. In most cases the list below doesn't state whether a given preference applies to all, or only some (and which), of Firefox, Thunderbird, Mozilla Suite, SeaMonkey, or even the now discontinued Sunbird: trial and error is often the only way to tell if some particular preference applies to your version of your application. This is a reference to the entries in about:config, where all user preferences can be viewed and modified.

This is not the place to edit your configuration settings. It appears incorrectly here due to technical limitations in the wiki software. The correct title of this article is about:config entries.

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