I don't know if there's a bug in my code or in B4A, but I'm unable to clear any activity mapping with clearPackagePreferredActivities. The goal is to remove my app as the default home screen. But when I use the reflector library to call clearPackagePreferredActivities with the package name as parameter, I get "ClassNotFound flm.b4a.playground" ("flm.b4a.playground" is my package name). Since many (Java) users reported that it works, I'm wondering why I get this message.