Just a quick heads-up that we'll be going down for maintenance and upgrades at around 11:30PM EST (give or take a few). The downtime is expected to be 30 minutes long - which will be our longest downtime ever. Most of our updates are either rolled out in minutes, or without any downtime at all. There are a few critical fixes and improvements that must be deployed and take quick some time to run. While the site is down, class widgets (embedded on your site) will not be responding. As soon as we're back up, they will resume normal functionality.
Sorry for the inconvenience.