pipExitFromCloseButton.kt

override fun onPictureInPictureModeChanged(
    isInPictureInPictureMode: Boolean,
    newConfig: Configuration
) {
    if (isInPictureInPictureMode) {
        // entered PiP
    } else {
        // keep track of background in onStart and onStop
        if (inBackground) {
            // User highly probably finished the activity in PiP.
            // execute finish logic
            finish()
        }
        // exited PiP
    }
}