* (bug 34876) jquery.makeCollapsible has been improved in performance.
* Added ContentHandler facility to allow extensions to support other content than wikitext.
See docs/contenthandler.txt for details.
-* $wgResponsiveImages is added to support images on high-DPI mobile and desktop displays.
+* New feature was developed for showing high-DPI thumbnails for high-DPI mobile
+ and desktop displays (configurable with $wgResponsiveImages).
+* Added new backend to represent and store information about sites and site
+ specific configuration.
+* jQuery UI upgraded from 1.8.23 to 1.8.24.
+* Added separate fa_sha1 field to filearchive table. This allows sha1
+ searches with the api in miser mode for deleted files.
+* Add initial and programmatic sorting for tablesorter.
+* Add the event "sortEnd.tablesorter", triggered after sorting has completed.
+* The Job system was refactored to allow for different backing stores for queues
+ as well as cross-wiki access to queues, among other things. The schema for the
+ DB queue was changed to support better concurrency and reduce deadlock errors.
+* Added ApiQueryORM class to facilitate creation of query API modules based on
+ tables that have a corresponding ORMTable class.
+* (bug 40876) Icon for PSD (Adobe Photoshop) file types.
=== Bug fixes in 1.21 ===
* (bug 40353) SpecialDoubleRedirect should support interwiki redirects.
recentchanges table.
* (bug 32951) Do not register internal externals with absolute protocol,
when server has relative protocol.
+* (bug 39005) When purging proxies listed in $wgSquidServers using HTTP PURGE
+ method requests, we now send a Host header by default, for Varnish
+ compatibility. This also works with Squid in reverse-proxy mode. If you wish
+ to support Squid configured in forward-proxy mode, set
+ $wgSquidPurgeUseHostHeader to false.
+* (bug 37020) sql.php with readline eats semicolon
+* (bug 11748) Properly handle optionally-closed HTML tags when Tidy is
+ disabled, and don't wrap HTML-syntax definition lists in paragraphs.
+* (bug 41409) Diffs while editing an old revision should again diff against the
+ current revision.
=== API changes in 1.21 ===
* prop=revisions can now report the contentmodel and contentformat, see docs/contenthandler.txt
* action=edit and action=parse now support contentmodel and contentformat parameters to control the interpretation of
page content; See docs/contenthandler.txt for details.
* (bug 35693) ApiQueryImageInfo now suppresses errors when unserializing metadata.
+* (bug 40111) Disable minor edit for page/section creation by API
=== Languages updated in 1.21 ===