Config Descriptions is a Firefox and SeaMonkey add-on that displays the source comments for advanced application preferences in about:config
The about:config page in Firefox and other Mozilla software lists a litany of default and stored preferences, some better managed through options dialogs, the rest hidden for advanced users.
The settings in here generally requires you to look up what they are online. Mozilla has its own documentation for many of its preferences in source comments in the default preferences files.
The Config Descriptions addon allows you to see them in about:config. It provides a quick way to view the information about preferences that is already shipped with your browser.
Config Descriptions is cross-platform and it works on Mac OS X, Windows and Linux.
· Firefox 10.0 and later
· SeaMonkey 2.7 and later