var _jq = "chrome://clpics/content/jquery-1.3.2.min.js"

// Load jQuery without messing with the toolbars.
//  Dunno why this is necessary, but it is and it works, so meh
Components.classes["@mozilla.org/moz/jssubscript-loader;1"]
            .getService(Components.interfaces.mozIJSSubScriptLoader)
            .loadSubScript(_jq);

If you just use a `<script>` element in the overlay, the browser toolbars are reset to their default configuration (at least with jQ 1.3.2).

FFExt: Safely include jQuery in a browser overlay

javascript, extension

JavaScript