-
-== External libraries ==
-=== Upgraded external libraries ===
-* Upgraded composer/semver from v1.0.0 to v1.2.0
-
-=== New external libraries ===
-* Added wikimedia/cldr-plural-rule-parser v1.0.0
+* Added CentralIdLookup, a service that allows extensions needing a concept of
+ "central" users to get that without having to know about specific central
+ authentication extensions.
+* $wgMaxUserDBWriteDuration added to limit huge user-generated transactions.
+ Regular web request transactions that takes longer than this are aborted.
+* Added a new hook, 'TitleMoveCompleting', which runs before a page move is committed.
+* $wgCdnReboundPurgeDelay was added to provide secondary delayed purges of URLs
+ from CDN to mitigate DB replication lag and WAN cache purge lag.
+
+=== External library changes in 1.27 ===
+==== Upgraded external libraries ====
+* Updated oojs/oojs-ui from v0.12.12 to v0.13.3.
+* Updated composer/semver from v1.0.0 to v1.2.0.
+* Update liuggio/statsd-php-client to 1.0.18.
+
+==== New external libraries ====
+* Added wikimedia/base-convert v1.0.1.
+* Added wikimedia/cldr-plural-rule-parser v1.0.0.
+* Added wikimedia/relpath v1.0.3.
+* Added wikimedia/running-stat v1.1.0.
+
+==== Removed and replaced external libraries ====