User.js file
user.js is a file that contains preferences that will be loaded into the Mozilla Application Suite every time the suite is started up. Each time Mozilla is started up, the valid preferences from user.js are copied into prefs.js, which Mozilla uses to store all the preferences for the current user.
The user.js file is located in the same directory as prefs.js. Valid preferences are via the user_pref command, as demonstrated below. // denotes a comment. Anything after these two characters on a line are ignored.
Following are a number of preferences and what they do:
// Turn on Type-ahead-find user_pref("accessibility.typeaheadfind", true); // Allow type-ahead-find to work on text by default user_pref("accessibility.typeaheadfind.linksonly", false);