docs: private ClassLoader expandClasspath(ExtendedEmailPublisherContext context, ClassLoader loader) throws IOException {
          List<ClasspathEntry> classpathList = new ArrayList<>();
          if (classpath != null && !classpath.isEmpty()) {
              transformToClasspathEntries(classpath, context, classpathList);
          }
  
          List<GroovyScriptPath> globalClasspath = getDescriptor().getDefaultClasspath();
          if (globalClasspath != null && !globalClasspath.isEmpty()) {
              transformToClasspathEntries(globalClasspath, context, classpathList);
          }
  
          boolean useSecurity = Jenkins.getActiveInstance().isUseSecurity();
          if (!classpathList.isEmpty()) {
              GroovyClassLoader gloader = new GroovyClassLoader(loader);
              gloader.setShouldRecompile(true);
              for (ClasspathEntry entry : classpathList) {
                  if (useSecurity) {
                      ScriptApproval.get().using(entry);
                  }
                  gloader.addURL(entry.getURL());
              }
              loader = gloader;
          }
          if (useSecurity) {
              return GroovySandbox.createSecureClassLoader(loader);
          } else {
              return loader;
          }
      }