2.516

This is an automatically generated changelog draft for Jenkins weekly releases.
See https://www.jenkins.io/changelog/2.516/ for the official changelog for this release.

🚀 New features and improvements

• JENKINS-75727 - Distinguish between primary and secondary actions in the header (#10729) @jtnord

🐛 Bug fixes

• JENKINS-75683 - re-introduce actions for Jenkins with custom action.jelly (#10678) @jtnord
• JENKINS-75727 - Distinguish between primary and secondary actions in the header (#10729) @jtnord
• JENKINS-75794 - Fix CodeMirror content being hidden after skeleton loading (#10754) @janfaracik

👷 Changes for plugin developers

• Implement SystemProperties.getDuration (#10561) @Vlatombe

All contributors: @MarkEWaite, @Vlatombe, @basil, @janfaracik, @jenkins-release-bot, @jtnord, @krisstern, @renovate[bot] and renovate[bot]