I'm in the process of developing a plugin. I created a Maven project from io.jenkins.archetypes:empty-plugin. The created POM contains:

    <properties>
      <java.level>8</java.level>

If I change this to 11 hell breaks loose because on line 485 in the parent POM org.jenkins-ci.plugins:plugin:4.28 there is:

                  <maxJdkVersion>1.${java.level}</maxJdkVersion>

and 1.11 is not a proper Java version. Hence it was not the best decision to define maxJdkVersion like this.

The latest org.jenkins-ci.plugins:plugin:pom:4.29 contains the same declaration on the same line 485.

The same applies to org.jenkins-ci.tools:maven-hpi-plugin:3.19, lines 292, 293.