I got the app called Foobar for playing audio. When it is playing and the screen is locked, it displays what I guess might be called a "widget" that allows the user to pause and play audio and move between tracks. I would prefer that this not be visible/accessible to the lock screen.
I have been assuming that this would be categorized as a "notification", but I might be wrong about that.
I have Settings>Notifications>Privacy>"Notifications on lock screen" set to "Don't show any notifications".
I have denied the Foobar application all permissions, including Notifications.
Is there something else I would need to do? If not, is the accessibility of the lock screen to third party applications an issue that the user needs to investigate for each individual app?
I installed the app using an apk file, in case that makes a difference. Thanks.