Hi Tim, If I got you right you want to lock your browser to be able to reach just one URL and nothing more? Or you get more tabs/urls when you press Home button and you want to specify just one? Vladimir

pref("general.config.filename", "mozilla.cfg");

defaultPref();	// set new default value
pref();		// set pref, but allow changes in current session
lockPref();	// lock pref, disallow changes

Maybe consider to lock the connection setting to use a PAC file and only allow this page. *http://kb.mozillazine.org/network.proxy.type *http://kb.mozillazine.org/network.proxy.%28protocol%29 *http://kb.mozillazine.org/network.proxy.%28protocol%29_port ---- You can use a mozilla.cfg file in the Firefox program folder to lock prefs or specify new (default) values. Place a local-settings.js file in the defaults\pref folder where also the channel-prefs.js file is located to specify using mozilla.cfg. pref("general.config.filename", "mozilla.cfg"); These functions can be used in the mozilla.cfg file: defaultPref(); // set new default value pref(); // set pref, but allow changes in current session lockPref(); // lock pref, disallow changes See: *http://kb.mozillazine.org/Locking_preferences *http://mike.kaply.com/2012/03/16/customizing-firefox-autoconfig-files/ *http://mike.kaply.com/2014/01/08/can-firefox-do-this/