Do not force plugin upgrades of recently detached plugins.
(pull 5311)
Stop bundling the Ant and Javadoc plugins.
Jenkins will no longer automatically install the Ant and Javadoc plugins on startup if a plugin depending on Jenkins 1.430 or earlier is discovered.
If you use such a plugin that also relies on the functionality provided by the Ant or Javadoc plugin (e.g., the RAD Builder and manage plugins outside the Jenkins plugin manager, you will now need to ensure that a recent release of the Ant or Javadoc plugin is installed.
Jenkins will attempt to load such plugins but may fail at any time during startup or afterwards with ClassNotFoundException or similar.
(pull 5338, Ant plugin, Javadoc plugin, RAD Builder plugin)
Improve performance when creating or deleting nodes by reducing queue-lock contention.
(pull 5402, pull 5412, issue 65308)
Improve support for update site-defined setup wizard suggestions.
(issue 65172)
Switch to sending POST requests by default for form validation URLs.
(pull 4623)
Add a Jenkins User-Agent header to outgoing HTTP requests by default.
Use jenkins.UserAgentURLConnectionDecorator.disabled to disable it if needed.
(pull 5368)
Sort available plugins by name when popularity is equal.
(pull 5359)
Honor the current folder when creating new views with the "New View" link.
(issue 56934)
Do not render full error responses in case of internal errors when validating fields in configuration forms.
(issue 65017)
Accept negative numbers in number input controls (regression in 2.274).
(pull 5341)
Improve reconnection behavior for inbound TCP agents.
(issue 64510)
Remove the hardcoded JKS key store so that other key stores can be used, like BCFKS from the FIPS version of Bouncy Castle.
(pull 5266)