Chrome does not pick up on time zone changes until a new tab is opened or the browser restarted.

JavaScriptTimeZone.js

/// Google Chrome:

var date = new Date();
// undefined
date;
// Tue Feb 11 2014 07:09:19 GMT-0500 (UTC)
date.toUTCString();
// "Tue, 11 Feb 2014 12:09:19 GMT"

/// WebKit jsc on the console:

var date = new Date();
// undefined
date;
// Tue Feb 11 2014 13:10:49 GMT+0100 (CET)
>>> date.toUTCString();
// Tue, 11 Feb 2014 12:10:49 GMT

// Chrome after pressing Command-Q, then restarting it:

var date = new Date();
// undefined
date;
// Tue Feb 11 2014 13:24:31 GMT+0100 (CET)
date.toUTCString();
// "Tue, 11 Feb 2014 12:24:31 GMT"