This is a summary of recent technology and site configuration changes that affect the English Wikipedia. Note that not all changes described here are necessarily live as of press time; the English Wikipedia is currently running version 1.44.0-wmf.3 (b4aac1f), and changes to the software with a version number higher than that will not yet be active. Configuration changes and changes to interface messages, however, become active immediately.

• An obscure problem with diffs was finally tracked down and (hopefully) fixed this week; it occasionally caused corrupted output from the diff engine. The problem turned out to be a version mismatch between the executable and operating system on some specific Wikimedia servers. (T11533 and many duplicates; was fixed without changing the code (just the executable), so no version number)
• Some actions now work correctly with respect to some pages whose name starts with / (such as Template:/doc). (r33742, bug 13822)
• The drop-down search suggestion box (enabled this week) now works in non-Monobook-based skins. (r33759, bug 13824)

• A range of new mathematical functions was added to {{#expr:}}: sin, cos, tan, asin, acos, atan, exp, ln, abs, floor, trunc, ceil, ^. The constants pi and e were also added. (r33780, bug 13216)
• The API now accepts prop=categoryinfo queries, which queries information such as a category's size. (r33914, bug 13735)
• A warning is now given when uploading an image with the same name as an image on Commons. (r33972, bug 889)

• Some HTTP cookies are now marked HTTPOnly; this reduces the effects that certain types of cross-site scripting vulnerabilities (if any exist) would have if they were exploited.
• The search box now suggests search terms. (There is an option to turn this behaviour off; see the 'Search' tab of Special:Preferences.)

• Internationalisation has been continuing as normal; help is always appreciated! See mw:Localisation statistics for how complete the translations of languages you know are, and post any updates to bugzilla or use Betawiki.