When starting up one can read the stack below (on Mac call the launcher from a terminal in order to see it):

Exception in thread "LibraryFolderWatcher(/Users/yjoan/Library/Application Support/Scene Builder/Library)" java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "accessClassInPackage.com.sun.javafx.scene.control.behavior")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:457)
at java.security.AccessController.checkPermission(AccessController.java:884)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.SecurityManager.checkPackageAccess(SecurityManager.java:1571)
at java.lang.ClassLoader$1.run(ClassLoader.java:502)
at java.lang.ClassLoader$1.run(ClassLoader.java:500)
at java.security.AccessController.doPrivileged(Native Method)
at java.lang.ClassLoader.checkPackageAccess(ClassLoader.java:500)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:455)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:367)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at com.oracle.javafx.scenebuilder.kit.library.util.JarExplorer.exploreEntry(JarExplorer.java:146)
at com.oracle.javafx.scenebuilder.kit.library.util.JarExplorer.explore(JarExplorer.java:70)
at com.oracle.javafx.scenebuilder.kit.library.user.LibraryFolderWatcher.exploreAndUpdateLibrary(LibraryFolderWatcher.java:235)
at com.oracle.javafx.scenebuilder.kit.library.user.LibraryFolderWatcher.runDiscovery(LibraryFolderWatcher.java:111)
at com.oracle.javafx.scenebuilder.kit.library.user.LibraryFolderWatcher.run(LibraryFolderWatcher.java:80)
at java.lang.Thread.run(Thread.java:744)


The policy file we use is directly coming from SB 1.1, no change has been brought to it yet:

grant codeBase "file:${java.library.path}/../-" {
permission java.security.AllPermission;
};

grant {
permission java.util.PropertyPermission "*", "read";
permission java.lang.RuntimePermission "accessDeclaredMembers";
permission java.lang.reflect.ReflectPermission "suppressAccessChecks";
};