Changelog

Major enhancement

Upgrade Groovy from 2.4.8 to 2.4.11. Groovy 2.4.9 changelog, Groovy 2.4.10 changelog, Groovy 2.4.11 changelog
Integration of Winstone 4.0: Upgrade bundled Jetty from 9.2.15.v20160210 to 9.4.5.v20170502. This removes support for the deprecated SPDY protocol. The --spdy parameter has been removed accordingly and Jenkins may refuse to start if it's set. full changelog

Bug fix

Jetty 9.4.5: Prevent the 400 Bad Host header error for HttpChannelOverHttp when operating behind reverse proxy. JENKINS-40693 , corresponding Jetty issue

Enhancement

Update the Mailer plugin version installed when updating from very old Jenkins releases to include the fix for SECURITY-372, the SSH Build Agents plugin for SECURITY-161, and the Script Security plugin for SECURITY-258. SECURITY-372, SECURITY-161, SECURITY-258
Freestyle projects may now list Pipeline jobs as downstream and trigger them, without needing to use the Parameterized Trigger plugin or reverse triggers ("Build after other projects are built"). JENKINS-28113
Internal: Define enabling/disabling in ParameterizedJob rather than AbstractProject. JENKINS-27299
Internal: Offer default methods on ParameterizedJob to have less boilerplate code. pull 2864

Changelog for 2.61