Netbeans project libraries - Compile-time libs vs Run-time libs

Question

Brief description

In a netbeans project, if I tell Netbeans that a specific jar file is to be made available on the compile-time classpath as a library, then, I understand that Netbeans would also make that jar file available on the run-time classpath. But this classpath lib "propagation" seems to work only in a non-modular project, and doesn't seem to be happening in the case of a Modular project (in Netbeans 11).

My experiment

I've created 3 simple, experimental projects, called ProjectA, ProjectB, ProjectC, in Netbeans 11. The IDE, as well as the 3 projects, are configured to run on Open Jdk12.

ProjectA

ProjectA is non-modular, and just defines pkg1.MyClassA

ProjectB

ProjectB is also non-modular, and defines pkg2.MyClassB which imports and extends pkg1.MyClassA. In ProjectB's Properties==>Libraries==>Compile, I have specified ProjectA/dist/ProjectA.jar file as a required classpath library. In ProjectB's Run options (ProjectB Properties==>Libraries==>Run) I have not specified this jar dependence. At runtime, MyClassA will be needed, because the main() method of MyClassB instantiates MyClassB which extends MyClassA.

ProjectC

ProjectC is Modular (created with Netbeans option NewProject==>JavaWithAnd==>JavaModularProject). It defines mod.world/pkg3.MyClassC, which has a main() method that instantiates pkg1.MyClassA. In ProjectC's Properties==>Libraries==>Compile, I have specified ProjectA/dist/ProjectA.jar file as a required classpath library, just as I did for ProjectB's dependence on ProjectA.jar. Also, I did not specify any jar dependence in ProjectC's Properties==>Libraries==>Run, just as in the case of ProjectB's properties. Also, I have specified --add-reads mod.world=ALL-UNNAMED in ProjectC's compiler option as well as a runtime JVM option, to enable the explicit module of ProjectC to access the unnamed module of ProjectA.jar, at both compile-time and runtime.

The Compile on save option is turned off for all the 3 projects.

What I expected

I expected to be able to successfully compile and run all the 3 Projects.

What I actually saw

ProjectA compiled successfully. ProjectB also compiled and ran successfully. ProjectC compiled successfully, but failed at runtime with NoClassDefFoundError for not finding pkg1.MyClassA. This runtime error goes away if, in ProjectC's Properties==>Libraries==>Run, I specify ProjectA.jar as a required classpath library (as I had specified in ProjectC Properties==>Libraries==>Compile).

My Questions

1. The Netbeans dialog window at Project Properties==>Library, says

"Compile-time libraries are propagated to all library categories"

. I understand that this was the reason why I was able to successfully run ProjectB, even though I had not specified any jar-file dependency at runtime for ProjectB, upon ProjectA.jar. So, why doesn't the same propagation happen in the case of ProjectC? Is it somehow because of ProjectC being a modular application? (Even if so, why?). Or is this a bug in Netbeans 11? (I did google for this before posting here).

2. What if, on some occasion, I wanted to stop Netbeans from propagating a compile-time library to run-time or to test-time? Is there a way to do that? For both modular and non-modular projects?

Here's the complete code

Code for ProjectA

package pkg1;

public class MyClassA {
    public MyClassA(){
        System.out.println ("Inside constructor MyClassA()");
    }
}

Code for ProjectB

package pkg2;

import pkg1.MyClassA;

public class MyClassB {
    public MyClassB() {
        new MyClassA();
        System.out.println ("Inside constructor MyClassB()");
    }
    public static void main(String[] args) {
        System.out.println ("Inside main() of MyClassB");
        new MyClassB();
    }
}

Code for ProjectC

Code in module-info.java

module mod.world {
    exports pkg3;
}

Code in MyClassC.java

package pkg3;

import pkg1.MyClassA;

public class MyClassC {

    public static void main(String[] args) {
        new MyClassA();
        System.out.println ("Inside main() method of MyClassC");
    }
}