I'm opening this as a continuation of https://issues.jenkins.io/browse/JENKINS-64341 as suggested. This is to add a few more details to Ryan's comment based on Mark's response.
We're seeing an issue with Jenkins 2.280-jdk11 where when clicking on the "Save" button in Configure System (even there are no changes made), it breaks and shows the error screen:
- Click Manage Jenkins
- Click Configure System
- Click Save button (don't need to make a change)
- Error screen shows up
- JDK Versioning: Jenkins was tested using on v2.280 using both jdk8 and jdk11. The error persisted through both versions of JDK.
- The plugin list from the last working deployment was used in all Jenkins version testing. The error still appeared, regardless of the list of plugins used.
- The error in the logs was related to a plugin. The solution given by https://issues.jenkins.io/browse/JENKINS-64341 to disable the related plugin was applied. On the next attempt, the same error with a new plugin reference was given. We were not able to reach a final iteration to fully get rid of the error during the minimal testing of this component.
- Jenkins Version:
- The following Jenkins versions were tested: v2.281-jdk11, v2.280-jdk11, v2.280-jdk8, v2.277-jdk11, v2.274-jdk11, v2.267-jdk11, v2.266-jdk11, v2.264-jdk11, v2.263.4-lts-jdk11, v2.262-jdk11
- Of these versions, the only two versions that did not contain the error were v2.263.4-lts-jdk11 and v2.262-jdk11
- This led me to believe that the error originated in a code change between v2.263 and v2.264.
- Note the "Rollbacks" for v2.264 compared to v2.263 in the Jenkins Changelog statistics: https://www.jenkins.io/changelog/