Redesigned login, signup, and Jenkins is (re)starting pages. Existing page decorators like Simple Theme Plugin will no longer work with these redesigned pages. (issue 50447, announcement blog post)
Replace single per-user API token with new system of multiple, revocable, unrecoverable API tokens with usage tracking. (issue 32442, issue 32776, blog post)
The
deprecated Jenkins CLI Protocol versions 1 and 2, and Java Web Start
Agent Protocol versions 1, 2, and 3 have been disabled. If you still use
these protocols (e.g. remoting-based CLI, or old slave.jars on agents), you need to re-enable these protocols after upgrade, or upgrade the clients. The same recommendations as in The 2.121.x upgrade guide for remoting changes apply here. (issue 48480)
Check
SHA-512 or SHA-256 checksums of update site and tool installer metadata
and core and plugin downloads if the update site provides them. (pull 3356)
Optional extensions are now loaded without requiring to restart Jenkins after installing an optional dependency. (issue 50336)
Upgrade
Winstone from 4.2 to 4.4 to update Jetty from 9.4.8.v20171121 to
9.4.11.v20180605, adding an option to enable JMX when running Jenkins
using java -jar jenkins.war. (pull 3422, pull 3497, full changelog, Jetty 9.4.11 changelog, Jetty 9.4.10 changelog, Jetty 9.4.9 changelog, JMX Documentation for Jetty, full list of options)
Upgrade
Remoting from 3.21.1 to 3.25 to have agents check availability of the
master's TCP Agent Listener port when connecting over TCP. (issue 51818, issue 52204, Remoting 3.22 changelog)
Upgrade
Bytecode Compatibility Transformer from 1.8 to 2.0-beta-2, upgrading
ASM from 5.0.1 to 6.2 to improve support of Java 9+ runtimes. (issue 51837, supported Java versions)
Update Executable WAR from 1.39 to 1.41 to allow running Jenkins with incompatible (too new) Java versions by setting the --enable-future-java flag. (issue 51155, issue 51994, issue 46622, Executable WAR 1.40 changelog, Executable WAR 1.41 changelog, supported Java versions)
Update instance identity module from 2.1 to 2.2 to improve Java 11 compatibility. (issue 51965, full changelog)
Update JNA from 4.2.1 to 4.5.2 to add support for s390x. (issue 52771)
Add a new CLI command enable-plugin to enable one or more installed plugins and optionally restart Jenkins. (issue 52822)
Add support for Zip files larger than 4 GB (Zip64). (issue 52356)
Add modification timestamp to files in directory browser views such as archived artifacts and workspaces. (issue 20998)
Export path to agent file system root directory in remote API. (pull 3206)
Jenkins remote API: Export fingerprints for builds which do not derive from AbstractBuild, like Pipeline builds. (issue 51667)
Some deserialization rejections are now logged on WARNING log level, instead of only on FINER. (issue 51666)
Instances of some item types could not be renamed (regression in 2.110). (issue 52164)
Don't
fail to archive artifacts when attributes cannot be preserved, instead
log a message and proceed without preserving attributes (regression in
2.120). (issue 52325)
Some types of builds, like pipelines, would sometimes run concurrently even when that was disabled. (issue 41127)
Developer: Introduce SimplePageDecorator extension point, which allows decorating the redesigned login page. (announcement blog post)
Internal: Update parent POM. Jenkins now requires Maven 3.5.4 or newer to build. (pull 3567)
Internal: Various improvements related to incremental Maven releases. (issue 51187, issue 51247, pull 3430, JEP-305)
