MediaWiki 1.17/Wikimedia deployment

MediaWiki is the software that runs Wikipedia and all the Wikimedia wikis. An upgrade to a newer version of MediaWiki (1.17) will take place on Tuesday, February 8th around 07:00 am (UTC). The most visible change for Wikimedia users will be the deployment of ResourceLoader.

ResourceLoader optimizes the use of JavaScript in MediaWiki, speeding up delivery of JavaScript by compressing it sometimes, and cutting down on the amount of unused JavaScript that gets delivered to the browser in the first place.

The installation of ResourceLoader may cause compatibility issues with existing JavaScript code. If you maintain JavaScript code on your home wiki, please see the documentation linked at ResourceLoader to make sure it continues to work with ResourceLoader.

The tech team have been doing their best to make the upgrade go smoothly, but some issues may arise. Please help us solve them by reporting them (see below).

Thank you for your support and your understanding.

What to do if you encounter an issue

 * Wait a few minutes; the tech team may be already aware of the issue and working on it.
 * Join the #wikimedia-tech channel on Freenode.
 * See IRC if you don't know how, or use Freenode's webchat platform.
 * If you encounter an issue after the upgrade, please report it on our bug tracker.

More information

 * Planned deployment of 1.17 branch on February 8 - Announcement on the Wikimedia Tech blog.
 * Draft release notes for MediaWiki 1.17.